whenever you finish a show, the last things you do are: get money and get your butt out of their house. When you're hired you are an entertainer not a guest.
If you have nothing to do after the show, why not stay after and have a little fun? It's fun to perform magic why not do it to anyone chance you have. Thats a great chance.
The key thing to remember is that if you stay, you are still THE MAGICIAN. So, you have to continue to play the part of the magician. Sometimes after a gig, I will stay for a few minutes to network with the parents and hand out a few business cards. This is when I will usually perform a few tricks just for the adults.
I left in my original quote because it is still true! Both mwnewman and magicman845 miss the point. You are hired as AN ENTERTAINER not as a guest. You are expected to do a show lasting for the contracted length of time, (i.e. half hour.) If you saty afterward and perform "a few tricks" you are giving away your product. Sorry, I am worth my $125/hr. But after the show I am out of there, if I stay around I am giving them a FREE show. Sorry I don't do freebies. My time is valuable and by hanging around I am telling the customer that I have nothing better to do, that I am not good enough as an entertainer to be busy. By leaving I am telling them I have another paid gig to go to, that I am a successful entertainer that is booked solid. Remember that appearances are EVERYTHING.