There's a lot for sale because people don't want them and they don't sell. Problem with cars nowadays is that it doesn't take that much to salvage a car. Insurance would rather junk the car than fork over money for the repair, then discover there's ongoing issues that cost even more money. So there are "good" salvage titles out there.
If you knew for certain that the damage was limited to bumpers and body panels, I'd say go for it if there's a heavy discount, and your plan is to run the car into the ground, and not try to resell it in the future. But chances are, you'll be rolling the dice that the salvage car doesn't have other, unseen issues like torqued frames, messed up electrical,, etc. If you get in an accident, will you trust that the air bags will deploy? That the frame wasn't poorly cut and welded, weakening the structure of the car? Etc