I've seen an 1100 disassemble itself like that, but I don't know what made it happen.
Have you tried contacting Wilson?
Wave, The short answer is yes.
Now having said that, I have a 1100 that has seen way over 60,000 rounds and not once had the extractor walked out.
Since some of the shotguns are less than stellar in regards to being de-bured before assembly, the crap (metal burs/parkerizing) has to go somewhere and in regards to the extractor, it just builds up underneath until it's partial blocked open (including spring bind), then one good hit and it will walk out.
Since you have to play with it anyway, check the spring channel, and the extractor retaining edge to make sure that they are clean of any crude/burs before reinstalling it. Also, take a good look at the ammo that you are running. If it tends to burn on the dirty side, it's not a bad idea to pull the bolt apart every 1000 rounds to clean the crap out (including pull the firing pin).
Note: If you are running any of the dot powders (red/blue) you will need to pull the FCG apart to clean it about the same time. The markers (which do not burn) get packed down into the FCG lower, and solvent/compressed air doesn't do a thing to clean them out once packed in. And before you ask, Clays is the cleanest burn powder you will find for shotguns if you are reloading.