Continuity mistake: In the restaurant, Frasier and Ann are at Kenny's table - Kenny puts his napkin down and leaves the table, while Frasier puts his cellphone away. In the next shot, the napkin has changed position on the table and Frasier is putting his cellphone away again.
Continuity mistake: After Frasier gets his fake phone call at dinner, he puts his napkin down, covering his plate and stands up. When the waiter goes by and Frasier asks for the check, the napkin is suddenly next to the plate and we can see the food left on it.
Continuity mistake: Frasier puts the tuna on the coffee table for Mr. Bottomsley and the cat jumps up and starts to eat it - he is facing the couch. In the next shot we see Eddie come into the room and suddenly the cat has moved and is facing Marty's chair - without enough time for the change.
Continuity mistake: When Ann says "Is that all bunny is going to eat," you can see a small piece of red food on Frasier's fork. When the shot changes and Frasier says "Bunny had a big Mexican lunch," the piece of food has gone.
Continuity mistake: During the opening credits of the show, Frasier and Roz are in Cafe Nervosa. Frasier has a fabric shopping bag, and in some shots you can see the leaves of one vegetable and in other shots you can see the leaves of two vegetables. These leaves are quite large and distinctively different.
Continuity mistake: During the opening credits, Roz and Ann are sitting in Cafe Nervosa - just before Roz says "Frazier" we see Ann put her mug down. When Frasier approaches, we see her put it down again.
Continuity mistake: At the end of 3-10 in the airport with Kate, Frasier says that he has an allergic reaction to cats but here he cat sits for Mr. Bottomsly.
Suggested correction: This has been addressed in the Questions section. Frasier is apparently choosing to deal with his allergies, in order help the cat's owner. It's also possible for allergies to be triggered by one cat, but not another. It depends on the amount of dander that the particular cat produces, and the level of Fel D. 1, a protein in their saliva.