Access cannot be limited to a service dog team, they are allowed to all areas used by other guests. They are allowed to use the self service food line (like a salad bar) and may not be prohibited from any communal food preparation areas. This does not mean they are allowed in the kitchen, but if food is being made out in the open, like a line at Subway they would be allowed to go through it. There are certain situations where access can be restricted, like a burn unit at the hospital, or a zoo exhibit where the animals on display are a prey animal and the dog’s presence would be disruptive to them.
It is important for you to know, if you are a business owner or manager at an establishment and are hesitant to grant a service dog access to your facility, these are highly trained dogs. Many hours of training are dedicated to bringing the dog different places and exposing them to environments where they will be around people and different sights and sounds. In fact, that’s what the bulk of most of the training is, not the commands. Also, most insurances will cover you (because of the ADA) and you are not financially responsible for any damages the dog incurs.
If a service dog is acting out of control, you are allowed to ask them to leave, but only after you have given them ample opportunity to rectify the situation! I was recently talking to Heather Turner, a SCORE mentor, who has counseled two restaurants and an inn. She advises that you when ask them to leave, that you can ask the “dog” to leave, but you can’t ask the handler to leave, if it’s a “real” service dog the handler will leave with the dog.