Not really, I mean I’d rather bag my own things, but you can just do that yourself if you want. It’s also worth mentioning that Americans tend to buy a lot more during a grocery run than most places, at least a week, maybe two, each time for their household. I also don’t need them to help me to my car, but it’s nice when they have the time to help if I did need it for some reason

It’s all very optional, you can go through without saying a word to anyone if you want to. I think that’s kinda shitty to not at least greet them, but plenty of people don’t bother