Is it normal to fondle the groceries?

I think you like textures and that this is in a way also a form of fetish. Normal, but you need to be careful. There are surveillance cameras and sooner or later people may become suspicious. The footage on those cameras can be obtained by news agencies, etc. What you should do is buy the groceries as well as other items of betting textures from other stores, take them home and touch them as much as need be. At home you can enjoy yourself safely and presumably in privacy.