Here's a reason: Almost every part of the dog is the "bite-zone." Shockingly, most dog breeds have the ability to reach any part of their body (or something touching that part of the body) very, very quickly. The only place you are absolutely sure to not get bitten is if you are standing directly behind the dog, and that's only if your reflexes are fast enough to back off when the dog rounds on you. Even then, most dogs are able to "catch their tails", which means they'll get pretty damn close to you very quickly.

This sounds like a corporate store. They have numerous rules to protect the groomers and dogs, some of which can be rather cumbersome. One rule in particular is that no dog can wear a muzzle for more than 20 minutes over the course of it's entire visit. Meaning you can muzzle it for 20 minutes and then not at all again, or for 5 minutes 4 times during it's visit. You can't just muzzle a known biter there, it's either suck it up or refuse the groom.

#68 - Which I actually find to be quite ridiculous. Muzzling does not harm the dog, especially because there are plenty of soft muzzles designed now where the dog can still pant and lick they just can't open their mouth wide enough to bite. No, muzzling won't traumatize the dog - unless you tackle the poor thing and be very rough trying to get it on. You just have to show them the muzzle is not a bad thing - which is pretty easy to do. Hold the muzzle up to the dog and hold a treat on the other side. The dog will step forward and put his/her nose through the muzzle and then receive the treat, thus making the connection that "Oh! This thing on my snout means treat and is a good thing!" Muzzle training, something every owner should do just on the off chance your dog may bite (which they will if they are in pain or very uncomfortable, even if they are the sweetest dog otherwise.) Correction: TRAINING, something every owner should do.

A determined dog can bite with a muzzle on, and many are adept at escaping them. Plus, putting a muzzle on can skyrocket the dog's anxiety. I've seen them buck like a bronco, twist and contort in ways that pose a risk of them injuring themselves. Often, it's easier to deal with the aggression and hope your reflexes are quick enough to avoid being bit. On a side note, (since some people around here are quick to jump to conclusions), gentle handling doesn't guarantee that a pet will be nice or cooperative. Often the aggression is fear-based, and caused by lack of training and socialization.