I have several types of Sunfish and I believe I observe routine snail eating, but not certain. Watching them do it right now.
Pumpkinseeds and Longears will eat/play/both with invasive trumpet snails. They will pick the snails up and if small enough suck the entire snail inside, swirl it around, and spit it out. I've seen them pick up bigger trumpet snails and it looks like they are sucking on it and then drop the shell. Sometimes they carry the shell from one place to another and drop it.
I've never seen one of those shells move again but it's also hard to tell because they are small. The fish themselves are not mature and the snails are too small for me to tell if they have been emptied. I have also observed my sunfish doing this with small rocks.
I can't tell if the sunfish are pulling the snails out of the shells or just picking up empty shells just like they do small rocks randomly. But I have definitely observed them picking snails off the glass and then spitting them after some chomping.
Dollar Sunfish and Pumpkinseed will pick clean any tentacles sticking out of any shell in your tank. I have mystery snails that were accidentally transferred into my native tank. I let about a half dozen of them go to see what would happen. They have no tentacles but have been going for over a year and routinely lay eggs which I have to remove. There's no way I've gotten all the eggs out every time so I think they may eat small mystery snails possibly.