In my opinion, a heat pad/tape is basically like having a hot rock to lie on to bask up the warmth. Except that it's heated directly by electricity rather than collecting warmth from above (a light or the sun).
So I think it's a very natural way for many snakes to get heat, as lots of nocturnal species wouldn't bask directly under the sun anyways. They'd lie on a heated rock. Or a heatpad, if such a thing is there for them!
Does this make sense?