It turns out they were already there since 3 o'clock eating and drinking. They already had the staff wishing they would leave. The good news is they were staying for karaoke.
They had progressed into drinking contests with the girls challenging the boys. The girls were winning. One girl had a very annoying loud voice that just wouldn't shut up. They ended up staying till 12:30-1 AM. One girl told me they had to leave because they had to work in the morning.
That's 10 hours in the bar. Is that some kind of a record?
I figured out why all the parties that reserve tables end up right in front of me. These are the tables the bartenders make tips from.
So everytime there is a party that reserves seats in the bar, they will always be right in front of me. Great.... 
