I could understand if airlines kept a blacklist for people who have animals out of control, but they don't even do that right now with their absurd overcharging. I could also understand putting down a refundable deposit and a $20-40 charge(though you can bring much heavier carry-ons for free).
The airlines' practices are indefensible. They are wildly overcharging and it is clearly a scam.
It is sad they are closing this loophole that allowed people to end run the scammers.