Don't let that last post get to you. I was actually shocked someone was not right there with you on this, as I was.

First off, its not your fault there isn't a good system in place to make sure that groups "legally" board together. This is something that the airlines must have noticed, and are working on or, more likely, have just decided its not worth it to set down system-wide procedures to fix and regulate something that hasn't caused that much of a problem.

Secondly, as you said, she had already scanned the passes. "Legally" she had to let you on. What if there was a snafu and the rest of your group got bumped, there was an airplane crash and ...

Finally, and most importantly, you were with Kids! Hello? What was she thinking? Perhaps, as an employee of the airline, the gate attendant was willing to "legally" do what was necessary to take custody of your children after forcing you to leave them alone, with her i.e. the airline. I wouldn't bet on it.

In fact, just to see how responsible the airline is for taking care of children in their charge, you know, just for future reference, perhaps you should have gone along with her idiotic request and told the kids to get lost for awhile. Just to see how the airline handled it, like how well they kept an eye on them. Now, that would have been interesting!