Very true,but then what do you feed your assassins?A couple of assassin snails would work really well in thinning out the population. They can eat around 2 snails a day and they won't mass produce like your normal pest snails.
Not overfeeding,regular gravel vacs,and picking them out when you see them is the easiest way to control them IME.It's not the fastest way to get them under control,but it will work.Setting traps with veggies also works well to get them more manageable a bit quicker.