I can't speak for the 4-strokers, but I fly 2-strokes, and all my engines are painstakingly adjusted to idle as slow a speed as is practical to keep the plug lit and transition good. When flying pattern in either practice or in contest conditions, I never killed my engine (on purpose anyway ), just trimmed the idle back to a slow tickover on final.
I'd much rather have a running engine and not need it than a dead engine and need it running. Like Tony sez, it really limits your options otherwise.
Taxiing is why our airplanes have wheels. Otherwise, why not just bungee launch and belly land? Nothing wrong with taxiing, where applicable. Beats walking out for it when you don't have to.

Landing deadstick is for newbies and control-liners.

Rick