I live in a neighboring state and we've had to increase our board as well. The price of hay (and feed, and deisal for the tractor, and...) didn't just raise and stay there, it's been increasing for quite some time. And from the looks of it, will continue to keep increasing. I have a feeling that extra $100 is to make up for the past AND FUTURE increasing prices. That way she isn't just increasing $50 every year.
I would be upset about not being able to jump in the nice ring. That is something she has control over. Can you talk to her about that?