Pre Authorized Damage Deposits???

So I'm curious if this is a COMMON thing at most places?? Or just as sketchy as it feels...?
I'm reading through a venue contract and it states I HAVE to have a credit card on file regardless of how I've made my FULL wedding payments. That they will pre authorize up to $6000 in extra fees that they can take after the fact if THEIR people deem you did not fulfill certain things in your contact or as a damage deposit....?? What stops them from Saying we didn't clean something and taking the funds anyhow??

Any thoughts/experiences or advice on this would be great?! And much appreciated. Thanks in advance lovebirds