just got me into thinking , as i recently done something like this (though just in a match). I had fun though killing everybody with a car while they are inside a house/building (dont know what happened but somehow i can see everybody in that specific area and can use cars to drive through houses/buildings its like no clip but just horizontally)
I've seen people use glitches in online GTA, it can be fun and depending on whats going on you may not get in trouble, depends on the people you make mad.