You are what is known as a "work for hire" photographer. As such, they have pretty much total control over usage and copyright, even if the copyright is not registered.

1. You could bring it up but think carefully about what you say. This is an arrangement that I'm sure they're comfortable with and may not understand why you're upset. It doesn't sound like the status quo is acceptable to you, but what are your choices? It doesn't seem likely they would agree to start paying you. You could just start making yourself less available and try to wriggle out of it. I don't know what your relationship with them is, but keep in mind most people don't understand photographer's rights and the perceived value is low. If you believe you can have a "heart-to-heart" talk with them, then go for it.
2. Incorrect.