Such things are common in sales in general. It's absolutely cutthroat. Salespeople, managers, everyone is in a Hobbesian all-against-all fight to the death for commissions. Crime and fraud are abundant. Personal attacks are not even that uncommon. Anyone who doesn't play this game tends to get muscled out.

It's obviously worse in some organizations than others, but it's probably harder to create a non-toxic sales org than to create a toxic one. Some organizations encourage toxic sales organizations because unfortunately it works, at least in the short term. It can do damage later but that's long after commissions have been earned.