As of right now, you would not need to fly out of Buffalo, you would just need ID to get across the boarder, and at the check in desk and such. But if you were to fly out of TO, yes you would need a passport.
But if I were you, I would just go them done. I mean if you are going for free dining, you have plenty of time, it makes it a lot less hassle to bring every piece of ID with you, and less hassle at the airport if they can just scan your passport. I fly out of Detriot and it just seemed easier if you had a passport, the person infront of me did not have one when I went to NYC for Spring Break and it just seemed like a lot of work now, without one. My advice would be just go get one, me and my BF are going to Disney in June, and flying out of DT but we went and got him a passport anyways. Just a little wait maybe an hr and half at the windsor office, and he should have his passport in 2 to 4 weeks. Trust me, you will need in the future, and its better to go get them now, than when everyone else is also in a rush to get one.