Because obviously the 'freebie' people aren't fans.
Or the stars are pretty flippin' busy and having to been several hours at a stretch to sign autographs would be a pain in the ass. Honestly... stars owe fans very little. She made the show, you watched it and enjoyed it. Seems to me like the deal was done. Not sure what any star owes fans after that point...
Dag, if "stars" are THAT busy, they should just stay home resting up from their busy schedules of trying to stay in the spotlight after their acting careers dried up after Trek.

Some should be grateful that they are remembered at all, so a number of them DO owe fans something.