I think Tristen means that if you used a heavier bowl, Bessie couldn't nose it around and make it spill.
So far, Spirit seems to like her bowl. I got her one of those reptile-type ones, where there's a reservoir that releases water into the bowl a little at a time. She hasn't managed to dump it over yet, and it does appear that she uses it more than the water bottle. At least the changing (or not changing) water levels suggest that's true.
I found a couple of flakes of bedding in the water this morning, but other than that it wasn't bad. Still, what kind of contamination potential am I looking at here? Should I empty and clean a bowl more frequently than I would a bottle?