Fast-food chains often introduce new/different food ideas for short periods of time. Hardee's used to do that with the mushroom 'n' swiss burger -- it'd come out 2-3 times a year. That didn't really make sense, as people seemed to love it, and it didn't require much in the way of extra supplies or space or something like that.

I think you're better off finding a place that consistently provides healthful alternatives, rather than rely on a fast-food place to do so occasionally. Subway is a decent option, for example.

But I know how it can suck when your favorite dish is removed from a menu. Good luck!