I have no idea what causes customers to linger at a table after they've already paid the bill. It pisses me off when people I'm eating with do it and it pisses me off even more when my customers do it. My managers want the table turned around so more customers will buy more food, and I want it turned around so I get another tip.
10 to 15 minutes after you've paid the bill is okay but don't linger around for hours. After I'm told I can leave I still have to wait on you to get up so I can clean the table. If it's lunch time, that means somebody else is taking the table after me and you're taking money out of their pockets. Find someplace else to go. If you must waste my time you could at least compensate me with a decent tip.