Keith a bike that crashes doesn't do that from the stand, it's usually at high speed or anything in excess of 30mph, hence they are built out of a hard pressed super durable compound designed to wear out during the momentum of a bike sliding on its side to protect expensive parts such as fairing, engine casings and forks/swingarms.

That's why the good quality ones such as R&G cost an arm and a leg, a kidney, spleen, retina, etc etc......

I've seen some "pricks" putting skateboard wheels as crasbungs on their bike and these totally shattered to sh|ts when they dropped the bike