If you're promoting a new movie/show/cd do you call around and ask if you can get on?
If you're promoting a new movie/show/cd do they call you and ask you to come on?
It's a slow week and the show need to fill their hour do they call publicists with the offer of $$ for celebrity 'x' to show up for 10 minutes.
If celebrity 'x''s career is in a slump do their publicists call around looking for a show willing to give their client a little exposure. And do they do it gratis?
Inquiring minds would like to know.