There are probably more well seasoned Hermes TPF'ers here who can give you a better answer. BUT personally I
wouldn't think they would consider you to be a store hopper if you make your intentions known that you'd like to switch your home store to be Palo Alto because its closer for you.
While I have heard SF might have better stock of some items (again, this could be up for debate because of the supply chain issue currently due to the pandemic BUT they are also a bigger flagship store so I really don't know how it is in SF currently) I really like how cozy & intimate the PA store is. I personally haven't been to the SF location just because I don't wanna deal with the parking, car break-in's, traffic from the South Bay, etc.
I think it's ultimately up to you if you would like to continue to make the drive up to SF, they are a bigger store BUT they might have low stock of anything at the moment as well too. If you want something closer and you don't mind starting new, then I think PA would be a great decision. Then finding an awesome SA who vibe with. They can then help order things for you if they are able to*. I totally vouch for Thao btw, she is so amazing!
*I'd just like to add - I think SAs can order things if its available from their warehouse but SAs are having issues with store transfers at the moment due to the shortage.
Hope this somewhat helps