In what way can any pilot waive the contract? It is one thing to pick up your version of overtime WITHIN THE CONTRACT but how can you just unilaterally waive contractual provisions and protections?
Lots of ways. For example, our contract limits the length of our duty day if we have a very early show. There's nothing in the FAR's that necessarily restricts our duty day, but our contract does. If the weather gets bad as the day progresses and that contractual duty day looks like its going to be exceeded even though it may be legal per FAR's, some guys will "waive" that provision of the contract with the crew desk to "help out." It's bull, but they do it.
We have a minimum rest rule on ANY layover of 9 hours "behind the hotel room door," even though the FAR's may require less rest. Some guys will waive that 9 hours behind the door to "help out" or for some sort of reward later in their trip.
There's two off the top of my head. There are more, and despite our management's behavior, we have some whores who can't help out enough. And some of these guys were flying overtime when we had guys on the street, which is just about as low as it gets.
It's funny, too, because when you confront these idiots, they get very defensive. Usually, the answer for their behavior has something to do with hating ALPA for reason x,y, and/or z. But when you say, "OK, I understand you're mad with ALPA for reason x, but what are you doing to express your displeasure with our management team's behavior?" you're met with a deafening silence.