Not all bumpers, and bumper mounting points, are designed for towing, and bumper forms may not be sturdy enough to attach brackets. Even where a baseplate/bracket installation scraps the bumper form and bolts brackets in its place, there are usually additional attachment points to take up vertical and torsional loads not considered in bumper engineering today.
I would expect to put "frame" mounted towing brackets, or a baseplate, on a Focus, before attaching a "universal" tow bar. Even then, if it came out at 24" width, I think I would prefer a fully braced A-frame like the Blueox Ambassador to a two-arm universal, as my low cost, car mounted, tow bar. Actually using an A-frame (private fab) on the truck now, going to a custom baseplate, even though I have a steel bumper that could ostensibly take a couple of mounting tabs, because I don't trust a collapsible bumper as a towing point.