You can't use bitcoin for buying stuff on the fly. Too much wait time cos too many conformations are necessary for it to be adopted by the mainstream brick-and-mortar stores. Full service Restaurants and bars do accept it cos you'll be sitting there a while. So yeah.. Any store where you normally would be in and out of in 5 minutes are never going to have any use for bitcoin. Those alts that were mentioned earlier are probably a better bet. In the long run, next generation currencies like Nxt with near-instant confirmation will likely be the staple for such transactions.