One is that since 9/11 the airline industry has gotten far more comfortable with calling the police to remove passengers. In some cases it's totally justified. But in others airlines are jumping to the threat of police force in order to "solve" issues with customers. Basically using the stick instead of the carrot because the stick is easier and costs less money.
The second problem is a far more pervasive problem in society where people excuse the use of force on someone simply because that person didn't comply with a minor request. This is how someone who didn't want to accept a ticket for selling bootleg cigarettes ended up dead. Or the guy just this week who got pummeled by a police officer for jaywalking. "Just comply" they say. Sure, but it doesn't mean you should be beaten, bloodied, or even killed for not complying.