Plenty of people do it, but because of negative opinion they remain quiet about it.
Personally I've never culled eggs and if I've had more offspring than I can deal with (which has almost never happened to me) I've generally just sold them cheaply in bulk or had friends help out. Generally I'd personally prefer to lose sleep getting stuff feeding and sold than going for other options.
I don't see any ethical issue with not incubating eggs, or for that matter humanely euthenasing reptiles and feeding them off to other species. For reasons inexplicable by any reasonable means, the majority of the vocal minority of herpers will scream blue murder if anyone feeds off humanely euthenased reptiles, while themselves feeding off rats and mice before having a nice juicy steak or lamb chops for dinner. I'll admit that I don't like the idea of it happening, but at the same time, I understand that I have no leg to stand on if I try to argue that this is somehow less ethical than feeding off rats and mice. As we all know, in this day and age you don't need to make any sense to kick and scream about something you don't like being wrong, and you'll probably even get people joining your tantrum.