But what exactly do you need regularly that you can’t get in local shops?

For comparison from one American of another: when I started reading this, the profile of /u/boobsb00bsboobs I built in my head--Californian, buys shiny things, tech-oriented, etc--told me that OP is relocating back to the States to live somewhere in the suburbs of Seattle.

Not in Seattle, of course. No, that might be too much like several cities in Germany. Must live in the suburbs, where the big box stores are supreme, craft beer is always IPA, and owning (and driving) a car on Washington State's crowded highways is a requirement.

Sure enough, I checked their post history and saw they'd posted in /r/eastside that they're moving to Redmond, one of the most plain-white-bread suburbs you can live in around Seattle without spending $5 million to buy a house in a rich enclave.

It's not about the local shops, it's about having felt like a fish out of water. And for a lot of Americans, the suburban car-oriented shopping lifestyle is the one that feels most comfortable.