More often than not, you either find a particular bar useful or you don’t and no one likes to have to click the “x” to close EVERY SINGLE TIME you end up on a link from that service. Most bars I’ve come across don’t let you universally just turn them off which results in the frustrating and repetitive behavior outlined above.
I’ve personally always thought there’s something a little skeevy about bars that hijack your browser (and in turn jack up my crucial Instapaper workflow) and I applaud Hoot Suite) for not only making it possible but making it easy to do by putting the control exactly where it should be for users to find it instead of burying it where they never would.