Well, they won't hustle you out, especially if you keep ordering drinks, but they do kind of count on table turnover to accommodate other ADR's, as you mentioned. I know there is a bar area; if you're just having drinks, you might want to move to there, or sit there in the first place, so you can get & keep a seat.
Several people have complained that they had an hour+ wait for seats here; it's probably due to the expectation by restaurant management that this is a restaurant, so people will eat & leave when they're done ordering. I didn't realize that guests might stay here for 4 hours or so, but I guess if you keep ordering drinks, then the restaurant is still getting its money. Even if some other Disser will complain that the wait for a seat was 2 hours!
Cheers!
Heather W