Let me preface this by first saying I agree that dogs should generally not be allowed in food serving establishments because their hair goes everywhere and nobody likes eating dog hair.

With that said though, I have never once seen my dog lick his own butt. What on earth are other people's dogs doing?! The closest my dog has gotten to licking his butt is licking around his genitalia, which I grant you is unclean as well, but he's fluffy and keeps the hair between his legs clean and un-matted. But butt licking?!

Now here's where I get down voted to hell, but I have to play devil's advocate lol. I would argue that kids are a MUCH larger vector of bacteria and viruses that are of concern to the average adult human than any dog. Dogs are gross, sure, but I'll take a lick from a strange dog over a strange toddler's sticky hands on me!

We should keep dogs out of food places, but mostly cause hair and allergies - if we're going to ban beings due to their gross factor though that list should be much longer (toddlers, homeless, anyone that didn't wash their hands after using the restroom...)