Where the heck are you eating where holding a table is a 20 minute endeavor? I rarely, if ever, spend more than 5 minutes in a QS line.
People who think they're doing the "courteous" thing by sending their family of six with stroller into the QS line are a much bigger problem than people sitting at the tables IMO. You can't easily maneuver large groups through those queues, so I think it's far more efficient to designate one or two people as the orderers and have the others gather napkins, condiments, high chairs, etc. then meet at the table.
The other thing... strollers don't belong in the QS line, nor do they belong in the seating area. Leave the stroller somewhere out of the way. (To be clear, my girls are 4 and 1 so I travel with a stroller, but I do it like an intelligent person.)