I have only been a GM for just over a year. The event is for GMs and up.
As I mentioned, I concede that I may be over thinking this. It just seems odd, but maybe not.
Thanks for pointing that out. For some reason when I read that staff were invited, I assumed it meant employees at Penny's franchises (but I guess that it applies to those who work in her central office). Perhaps you could speak with senior managers who have attended before to get an idea of how strict the policy on non-spouse partners is. Also, keep in mind that when communicating via e-mails in a business setting, manager types tend to be more careful (you probably do the same when communicating with those that work for you), because such communications could be used as evidence should something happen down the road. Here, I'm referring to corporate e-mail accounts, not private e-mails - I don't know what kind of e-mail accounts you and Penny use.
Maybe if you speak with Penny in person (one on one, not Republican/Christian vs. gay man), you can flesh out the issue better and with less pressure to be so formal in communication. There's always room for flexibility. In the event that she becomes rigid during your conversation (whether in e-mails or in person), you certainly have the right to ask for proof of the 20-year policy she mentioned, etc. This is a difficult decision to make because you then jeopardize how you are perceived by Penny and your colleagues during your continued employment. Hopefully you will be able to resolve this issue through a rational conversation. If not, it's up to you to decide if your time and energy are best spent "battling" the issue, which you have every right to do.