It’s not that Spirit is being nice, if f they could charge for a small food bag being carried on board they would in a heartbeat. It’s an FAA rule that bistro sized food bags are exempt from the carry on restrictions.

I always brown bag it on my flights, I carry a small six pack sized soft insulated bag with sandwiches and snacks and I never have been questioned about it. I even put it on top of a roll aboard so it is clearly obvious it there.

Mr. Elliott