Here is my list:
I buy shoes - I have massively huge feet and the choice (if only in cheap places!) is much better in the US. I often find the brands I buy in the U.K. for £80 are about $20 dollars at Payless (they aren’t great quality shoes but I’ve havent got much choice!
Cake decorating supplies, baking supplies and sprinkles - fewer restrictions on food colourings so there are some different things.
Spice mixes, bbq sauce, Chilli sauce, hot wing sauce, Mexican ingredients.
Williams Sonoma is lovely as a PP said, expensive but I could buy everything!
I also try to have a book shop browse, different cook books, magazines, stationery etc
Christmas decorations - we try to get a bauble with the date on from most places we go
Outdoor supplies and clothes, I like LL Bean