Is this an actual question? I’ll answer it anyway: because they had nothing to do with financial market risk shenanigans and just wanted to get somewhere.
Also with secured claims. What are they secured against? That is what is the collateral defined. If it is not cash... Well they will get their claims when collateral is liquidated.
Aviation has stricter laws when it comes to customers. I don't have citations off the top of my head but it's not a normal customer-business relationship.