I've often wondered the same thing about visiting quilt shops in other areas expecting to find something different. Twice I've gone to shops while traveling. Once in Louisville and while I did find a RED batik I'd been looking for I found the prices much higher than at home. The other time however I spent a LOT of money on quilting stuff BUT that was on a trip to Paducah ... just couldn't resist the incredible sales ($3, $4 and $5/yard!).
There are some places I will travel to where I will make an effort to visit local shops as part of my travel plans (Lancaster County PA, and any foreign country), but other than that if I "find" a shop I'll visit but I doubt it will be high on my agenda if other activities beckon.
I have to add though that I come from an area with a large selection of quilt shops - large and small - within a 2 hour drive. I have two large shops that are 40 minutes from my house.