This is very much something I think my grandparents have passed on and it's slowly pushing me over the edge. My DM is ok financially but refuses to pay more money than she absolutely has to for anything.
She likes to get different things from different supermarkets. She doesn't drive and she spends her weekend going between Sainsbury's, Aldi, Asda, M & S and Tesco to do her full shop. This involves many bus trips.
I will happy take her by car to do her shopping but I can't cope with the multiple shops. She wanted a specific bar of chocolate and in Asda it was £1.50 and she refused to get it as 'its only £1 in Tesco'. She would rather check out, drive to Tesco (or get the bus if she was by herself) and go into another supermarket on the off chance they had it, to save 50p.
I'm finding it harder as she gets older to let her keep going out herself with her trolley bag. I get her an online delivery for heavier items but she seems to sort of revel in this hunter/gatherer role. During the pandemic when you were meant to limit outings she was constantly roaming different supermarkets and wasn't going to let a pandemic get in the way of 'I prefer Aldi brand of XYZ'.
Is this an age thing? Should I be more accommodating? She expects me to do it to and when she's rummaging in our fridge (!) tells me I've overspent by £2 by getting whatever from this one shop instead of shopping around.