Why do hot rocks burn, and heat pads not (as much)

[Stewart_Reptiles]

Reasons given by lizard people usually are that reptiles don't feel heat on their bellies and don't know it is hot, but snake guys use UTHs.

This is true for some species including BP (which is why they often get burned) however it applies regardless of the heat source used if not controlled. T-stat allow temp control, prevent overheating which lead to burns and most importantly lack of T-stat can be a serious fire hazard.

Glue gun ?

Sooner or later especially since the glue will warm up it will dislodge itself not worth the risk when there are supply out there that are safe when used properly.