That's not the only reason to use dampits though. String instruments are very sensitive to humidity and dryness. Basically, both are bad for them. Once it gets too dry or too humid, instruments can have open seams which usually keeps widening. Luckily my violin has been very strong against such issues (considering the age of my violin, I have to say I'm very lucky)
Sometimes I immerse mine in water this way. You only need to give it water when it dries up. Depending on the humidity, I usually do that once or twice a day.
When I use one dampit I put it in the hole of the G-string side. It could come out of the hole while you play due to some vibration on the instrument. When that happens from the E-string side hole, it will be in your way to bow.