We get a few occaisionally that ask about bagging; I tell them we keep on top of things so you don't have to bag. Only time we bag is in then fall, or in summer when rain holds us up, & we can't get to it in time. Even then we usually just double cut.
If a new customer demands bagging, you better believe the price is gonna reflect it. If not then too bad see ya. "I have others waiting in line......"
I can see the reason people like yourself and other refuse to bag when possible. My work area, very few people don't bag. Clients just expect it here in the San Francisco Area. Myself, I see the light now. This last month I have been mulching whenever possible. Gotta see how messey it's going to be during our wet season. The only time I'm going to bag is the fall leaf dropings and long wet grass.
Stones right, sometimes on smaller accounts, its just easier to bag, especially if you don't have a mulching plate or deck. If theres not a lot of room, it takes longer to worry about where your discharge chute is shooting into now! Bigger lots that allow it, and you can keep up on them are more easily discharged.
I guess if your contimplating buying one, it depends on your territory. If you can use it for fall cleanup, than go for it, if the customers will pay more for bagging weekly, go for it! As long as there is a market for it, it'll work.