Well, this post is not a total moan, so I guess it won't harm to say the airline in question was EasyJet, flying from Luton.
As was mentioned, I think we were the "compulsary" passengers per episode of airline that get turned away - cameras in fact there and filming everything going on. Maybe this is the reason why we were at least offered flights the following morning at no extra cost (except overnight accom.). I wonder if this is standard practice?
I understand the fact that rules are rules, however, attempting constructive debate, feel that in this situation they could have tried to help out and enhance a "helpful" reputation. Its a couple of minutes to the gate (walking) and everyone had hand language. The other passengers would not have boarded yet, the plane was not full and there would have been no delay for the aircraft. I know (personally and from others) of many occasions where this would not have been an issue. If you think about it, it would probably take longer for them to put lugage in the hold when we arrived just one minute before close, than it would to let us through with hand lugage a minute after close.
Maybe they could have staggered check-in close for those with and those without hold lugage. No doubt some will argue this is moving the goal posts again, but in reality hand lugage only must be quicker, and its one less thing that passengers could use against the airline when not being allowed through.