Are your city’s public parks spilling over with vagrants, junkies, and hookers? Here’s an idea that could only originate on the West Coast: pay people to hang out in them. Call it preventive busking. Last week Seattle began paying street performers to busk in five urban spaces and parks, apparently hoping to liven up the sites with crowds and shoo off the unsavory element that normally collect in them. In the civic “experiment” run by the city’s Parks and Rec Department, musicians and other artists — including visual artists and vaudeville-style performers — are bankrolled to the tune of $30 to do their thing from 11 a.m.-2 p.m., and they get to keep the tips. It’s certainly creative thinking. Now, how long ’til they figure out Bumzy McBoozalot the Clown is actually a hobo on the city payroll….