What if you can't choose?

Tonight I had a training session for my part time job, where I manage a program that prepares taxes for low income families. Its the most personally gratifying work that I have ever done (despite its challenges, which I'm sure you will all hear PLENTY about once the tax season starts). I really enjoy being a part of this program, really I do.
So tonight, I left right from my 9-5 to go to this training session. At the last training, they had a really nice meal for us: rotisserie chicken, green beans and potatoes (and plain caesar salads for us veggies). Last training session, I had a salad almost dry and half of a piece of cornbread. It was healthy enough and it filled up me up for the rest of the afternoon. So I was expecting something similar tonight.
Instead, we got pizza. Now, I already had my allotted pizza treat on Saturday (and a leftover piece on Monday) so the last thing I wanted (let alone NEEDED) was pizza. I was SO hungry that I ate a slice of pizza. But then I was still hungry and had 3 more hours of training left, so I had another. I don't mean to sound ungrateful, I do appreciate that they feed us. But, if given the choice, I would not have selected pizza for dinner. And, thinking I was getting something else, I didn't plan ahead and pack a dinner.
We talk so much about the choices we make every day and the challenges that come alone with them. So what do we (you) do when we don't have the option to choose? Do we intentionally eat something we don't want to, and get back on track later? Or do we become really unreasonable about our commitment and find a way to get something else?
I had a very interesting discussion earlier this week in which someone challenged me to the idea that unreasonableness in our commitments (that is, the idea that we go beyond what we think we can do to stick with our commitments) is what ultimately makes us successful. So maybe I should have excused myself for 15 minutes to go hunt down a salad. But next time I'm in a situation like that, I will. And not because I'm afraid that 2 pieces of unplanned pizza will kill my goals. Because I am committed enough not to look for (and take) the easy way out, even when doing so will make me look completely neurotic.