Yep, had this problem with one of those "ball feeders". My solution was to put it in bathtub.

We have a ball feeder, but this ends up not being a problem; he eats every scrap of the food that comes out, even if there are smaller crumbs. I guess it helps that we feed him on a wood floor, not carpet, too.

I feed on a wood floor and I have a Roomba. Great combo.

True, there can be a few bits here and there. Used to have some food left around but now he seems better at getting all of it. And I try not to fill them up too much anyway. The ones I linked have an adjustable opening, so I use the smallest setting, lets less food out at once which helps in this area too.

Something to be careful of is where you put it. For a while I would put them on the rugs, or hidden near rugs, and he would eat on the rug. I think this led to ingesting too much crap (fibers, hairs, whatever) which led to some, uh, clingers, shall we say. Since moving exclusively to hardwood floor areas, it has gone away.