As a former JSer on CAL, I'd say 85 to 90 percent of the time I was treated with kindness when checking in. The other percentage I've heard it all:
"Didn't you get a seat?"
"Why the f*ck are you here?"
"What's wrong with you friggin' RJ guys?"
"Did you talk to the agent? That's how we operate here."

And so on, and so on.......So just because a few CAs don't like the upfront check-in doesn't mean the rest don't want you to talk to them.