oswiff

So last weekend I went to get my car from my parking garage. I park in a public indoor lot in Manhattan next to my building. When I went to take my bumper pads off the car, I noticed that my grille was pushed back (out of it's tabs) and the star on the grille appeared to have bubbles (see photo - the bubbling is right in the center of the star). I thought at first that the garage attendent had backed another car into mine but there is no damage other than the bubbling. There are no cracks, no marks on any part of the front of the car.

I ended up getting it replaced today under warranty, my dealer took a look at the grille and replaced it for me saying they didn't no what it was but without other visible damage they just replaced the grille under warranty.

My question is, has anyone else seen this or experienced it? I think the grille is plastic with a chrome coating. I think one of two things happened, I either did get bumped into in the garage or I just had a defective finish.

If it helps, I hand washed my car the weekend before I noticed (i only take the car out on weekends) and I thought maybe the soap had a adverse effect with the chrome, but I thought that would be a bit of a stretch but I really don't know.

It doesn't really matter now because I got a brand new grille courtesy of my dealer but I just wanted to see if this has happened to anyone else or if anyone can suggest what might have happened so I can avoid this in the future.