2002 Bravada front bumper assembly

i have an '02 Bravada with a very loose font bumper assembly. i'm hearing vibration when i drive and i suspect the bumper has a lot to do with it. i checked it out, and the whole assembly is essentially held up by a bunch of plastic tabs. that's right, plastic. a lot of those tabs have been sheared off. to me this seems like a relatively easy fix, but i'm told that it could cost a couple hundred bucks. for that kind of money, i'd expect something better than new plastic tabs. also, i've been told that i need to take it to a body shop to get this done.
anyone have any idea how much something like this should cost? and why GM would have designed something like this using small plastic pieces? my only guess is that the bumper is supposed to have some give if i bump something, plastic will have more elasticity than metal??? just a shot in the dark...

It is most likely designed to shear off in case of an accident. Cars built now-a-days have to meet government crash standards and are covered in crumple zones, to absorb impact and protect the passengers. If most of your tabs are already sheared off something has most likely hit the front end and/or the car has hit things. Since no damage is noticable other then the looseness of the bumper cover it may be that the car has pulled to close to the garage a few times. People seem to thing that its a good thing to see a car in an accident and have no damage, but that just means the people in the car have a higher chance of being hurt. Ever see a race car after an accident? There is nothing left of the car and the drivers usually walk away unharmed.

that all makes sense, only problem is that this car has never been bumped by us (we bought the car new), so unless we got bumped by someone in a parking lot or something like that, then i don't see why most of the tabs would be busted. anyway, will take it in for an estimate on monday. if anyone has any idea how much something like this should cost, please let me know. it doesn't seeem like it should cost much, just replacement of the tabs, nothing else is damaged as far as i can tell. of course labor costs being what they are, 30 minutes work could be $50...

Exactly what tabs are you talking about? Do you mean tabs that are the same material as the bumper/bumper cover and slide in a slot, or the plastic push in type that kind of work like rivets? If you mean the type that are like rivets, you should be able to pick up some at just about any chain type store like autozone, murrays, etc. or any better parts store should also have them. If they are part of the bumper cover they will either need to be welded back on by someone who knows what they are doing and has a plastic welder, or the entire cover would need to be replaced. I have not worked on a 2002 or newer so I am not 100% what is there. If you just have to replace the push ins, thats nothing and not expensive. If you need to replace the bumper cover, they are not to expensive, but getting them painted to match will cost. They come without paint and since they are plastic/rubber, they are flexible and need a flex-agent mixed in with the paint to keep the paint from cracking.