To be fairrrrrrrr.....
The beams are wider than normal phasers in most situations. Like mariner cleaning carbon off slightly harder carbon or the crew cleaning the crystal graffiti off the ship.
I could see that being an energy-intensives thing though, and having worked on handheld high-current devices, I could totally see limiting the beam power/width settings to ensure you don't melt your hand. Or accidentally trip the overload setting...
here's a crazy idea: dedicated cleaning beams that make that kind of thing a "boop and we're done" situation. Or like.... Use the rifles. Those have to be able to handle more power, right?