In fairness to the airline and airport, I wouldn't have put in any additional permanent infrastructure to accommodate a once-in-a-lifetime event. I wouldn't put any money into it even for a once-every-four-years event. When 8000 people show up at the queue at the same time, there will be waiting, regardless of how many stations they might have had in place. Nobody is going to engineer systems around that. And TSA, don't even get my libertarian juices flowing on that disaster......
We have always left a tip for our guides whenever we go on a trek since most of them are college students and these camps don't pay a high wage it more of a labor of love for the guides. Normally I ask everyone give $10-20 for adults and $5-$10 per scout if they feel the need to do so. We then have everyone sign a card with a short thank you and our youth trek leader presents it to our guide. Our last trek was awesome and most everyone gave more than normal so out guide ended up getting close to $300 which when he thanked us he was tearing up since he was a grad student who lived on very little so a not to accumulate a huge debit while finishing college. Its a small price to pay for someone who might have a life long influence on your scouts life.
We have always tipped our Sea Base guide or rafting guides after our trips. We did not tip the boat captains. We don't do it blatantly, but discretely. For the most part these young men are not highly paid, and if our tip can pay for a pizza or the like for them, we've done a good thing. We build it into the fees for the trip
In addition to complaining, be sure you ask for compensation if your flight was excessively delayed or cancelled. There is a website that can help you understand how that works and that says they can help you with claims: https://www.airhelp.com/en/