Yeah, the "singles line isnt for everyone", it's for singles, and your "current system" is entitlement.
Ski singles lines exist to efficiently pair-up (or quad-up) skiers for efficiency at loading chairs, not so four teenagers or 20-somethings can cut hundreds of people and wait in a 3 minute line instead of an 8 minute line.
I wish more ski areas enforced this, I can probably count on my 2 hands the number of times I've seen singles line cheaters booted out of the singles line and sent to the end of the line.
I guess I am surprised to hear that people actually have an issue with this...Personally I don't see it the same way, nor do I have an issue with it. Curious how the heck can you enforce it !?!?