A couple of years ago I came off a freeway exit and dropped a tire in a pot hole (invisible because it was full of rain water). One of the elbows exiting my catalytic converter caught a rock and I had a very noisy ride the ten miles it took to get it home.
Then it cost $1,000 just in parts to replace the head pipes, the catalytic converter and the pipes between it and the mufflers.
Okay I'll admit this was on my Corvette and it might be a little low and parts are a little more expensive, but it sure made me stop and think about how low I allow any parts to hang under any of my vehicles.
And maybe some of the parts needed to be replaced anyway, but they might have lasted another year or two if it weren't for dragging things on the pavement.
I didn't get a ticket but as loud as the car instantly became it sure was a possibility.
This is why so many show vehicles have air bags. You can lay frame at the show and in the parking lot, but still have enough ground clearance to drive without throwing sparks and breaking parts off. If you are going to end up with less ground clearance than a pop can standing on end, you're very likely to have problems with things dragging going in and out of parking lots and driveways.
I must be getting old, I sure sound like an old man...