Many moons ago a skipper of a renowned carrier travelled ID-pax on a smaller national carrier. After push-back, seeing the wing nicely covered with snow and realizing they were not deicing, he asked the hoastie to tell the captain just that, identifying himself as a fellow captain. She came back reporting the PIC said the passenger should mind his own business. The skipper, as able body beeing seated at a emergency exit, then opened this overwing window to avoid take-off.
Outcome of the story: He got arrested and convicted for endagering flight operations.
The flight later took off deiced.
Food for thought