Debs,
Your comments point out both sides of the issue here.
"anyone has rights to any area for photography if they are off private land."
"It does suck when you wait (paid or not) to get the perfect shot and then have it ruined."
For me the issue is one of courtesy and consideration. We all have the right to take pictures where we want, but since the trains we were all photographing were made possible only because someone paid for them, we probably should try extra hard not to get in the way.
Would you take photos of a wedding being held in a public park? You have a right to be there, but common courtesy says you shouldn't do it. Same for standing in front of the photo line and claiming you got there first, as has happened on several occasions.
Paying for the train doesn't give anyone special privileges, but it ought to at least earn them some courtesy and consideration. If they hadn't paid, you wouldn't have your own photos either.
Michael Allen