You are right, though. LOLWe've been to quite a few restaurants in the US that charge $150/person for reservations and then just apply that to your bill. It essentially forces the bill to be $150/person at a minimum. Personally, I don't mind as it ensures we will have a table waiting when we get there and we already planned on spending that amount.
$5000/table is definitely on the higher side, but if it's in a popular tourist destination AND folks are willing to pay it, then more power to them. Great business idea.