I wouldn't use the seat cushions, but it is a pretty solid idea, IMO.
I have no hard opinion on the cigarette topic, but if the policy is going to change on whether or not you can bring them in, or some are going to enforce it and some aren't, it needs to be in writing. It really aggravates me when people get hassled for things that aren't specifically banned. For example, every game for the last two years, I brought in a half sheet of blank poster board and a marker. No problems from anybody, until the jets game last season, because according to the officer that took it from me in the concourse, I could write profanity on the sign. Whatever.