how can that be bad for them? its like taking your ram out every time you shutdown. it reduces the risk of phyisical shock and damage, and also dust entering the circuitiry.
how can it get hot? if it is plugged in and there is no heating, implied by not accessing it, implied by low voltage. Even if it is in use all the time, the card wont take damage as the cards can take a lot of physical strain, as this is what they were designed to do.