How do I manage 90 yr old FIL expectations regarding running errands?

Mich56: Your FIL is a fortunate man with you taking him grocery shopping. He will have to opt for a ride share, Uber or Lyft if he desires to go daily.

My mother, who chose to live alone many states away from me, used her town's senior center transportation van for WEEKLY grocery trips.

Dont feel terrible. Tell him it's not you, but the gas prices are out of control right now. We can no longer run out to pick up 1-2 items and multiple stores and trips. We must conserve. He will have to buy 1-2- extra items as back up, so he won't run out of the staples. It is available when needed.
I think he wants to go out, to be out. It gives him something to do. A social event, to chat with you, a ride in the car, something to look forward to, and look at selections in stores.

My dad could spend 2 hrs in a drug store, looking at every item. He even involved staff to explain items to him. One even looked at me like help me. So I told him she must get back to work. So trips are social excursions. Its probably the only outlet they have if they dont go to church. Other than doc appts.
He's not going to say I'm lonely, watching TV 24/7 bored out of my mind. He might think family will come over if I need an item, as an excuse to get you to spend time with him.

If you suggest picking up 2 of that item, see what he says. If he gets mad, Its the outing he craves. It gives him a focus, something to do, and have fun. He'll get over being mad when he wants to go out again.
I'd blame the gas prices. Perhaps calling more would alleviate loneliness? Or getting a person to visit? High school and college age kids can spend a few hours and chat and cook him a meal. They can put that on a college aplication.
Or maybe setting up a meal date to be social. Have it at a regular day/time. Tell him to think of a recipe or something he can look foward to eating. Probably looks like another chore, but he won't be around forever. I feel bad I didn't spend more time with my family. I let life get in the way. I told my husb to go over 1x a week to take his mom out, have lunch, and do a chore around the house. She wasnt eating, loosing weight and had other issues. And now she does. I told him I regretted not spending more time with my family, and now its to late. He agreed he calls more, and get his brothers to do that too. She now has that to look foward to at a specific times. And he not just showing up for doc transport. That isnt fun. She's doing much better now. Good luck.

Order groceries online and have them delivered to his home. I have used this option for myself whenever I was ill with the flu. It works like a charm...you may have to pay more but it is worth it.

You've set the availability that you can manage so let your FIL deal with it. If he gives you the silent treatment, then so be it.

Honestly, these elderly (my own mother included here) and their demands is majorly annoying. Instead of being grateful for the help and care that they need and are receiving, they dig in their heels and refuse to conform to the limitations of their condition.

I'm 64 years old and I can't leave my home for days at a time because I don't have sitters every day. It might be 4-5 days between trips out - it doesn't matter what I may "want" or "need" to do - I have to wait.

I'm sure that we could make a sad list here of all of the freedoms and desires that care-slaves (yes, that's how I am now referring to myself) have to give up in order to provide care to a LO.

Therefore, I have very little time for pouting and petulant elders who don't get their way.

Peace.

Stick to your decision of how often you will take him shopping. Ask other family members, neighbors, members of faith community to take him out for "short errand runs" on other days of the week. If others will visit him on a weekly basis so he has a visitor for most days of the week, he will get his "shopping needs" met as well as his socialization needs met (the reason he is mad at you).

I completely understand. I do find that my own Mother expects everyone to jump to her demands. I would stick with one day a week for grocery and medication runs when possible. I do feel that a lot of their demanding expectations are because of their generation. There are too many similar complaints. I would definitely use as many trusted delivery services as possible. Too, I believe loneliness is a big issue. My Sisters MIL is 95, and does fine if someone picks her up every afternoon to head to the pub for some wine. She doesn’t want to be alone for very long during the day. They hired a caregiver from 11am-3pm-Monday through Friday, and then one of her three children take turns getting her out most days in the afternoon and weekends. She’s very content now. Not everyone can have it so good! If they would be open to using zoom or FaceTime and talking to friends and family, I think that it would help combat the loneliness some. Most don’t like using computers. FIL might do good with adult day care if one is available and can pick him up a couple of times a week. All the best in keeping him happy.

'Mission Creep' is what this is.

Had this with one LO..
One ride & back to a regular event. Then the add-ons..
+ home tidy up
+ rubbish out
+ help with dressing & footwear
+ outing
+ errands on way home eg post office or groceries, hints for lunch or even another appointment booked withon 1 hour.

Boundaries.
One trip was my offer.
Arrange all 'that' from others.

Now.. has multiple aides for homecleaning, personal tasks & transport.

LO's needs are met.
I am no longer overburdened & resentful.

Just say “NO!” Why is this even a serious question? Let his silly calls go straight to voicemail, and let your husband deal with it. Or inform the old coot that there is a marvelous modern invention called “delivery service.” If he wants to pay for that, well, he can sign right up. Sounds to me as if you have spoiled him. That needs to stop!

Your FIL thinks that you are his errand boy and this is why he wants you to be at his beck and call. It’s time for FIL to realize that you have a life of your own and you cannot be at his beck and call. Tell your FIL to write a list of all the items he needs to purchase and you will take him to the grocery store once a week to buy the items on his list. Tell your FIL that if he does not abide by your rule of taking him to the grocery store once a week since you have your own errands to do, then he can order his groceries online through DoorDash or Instacart.