Does mildew still make the Miami airport one you can identify by smell?
The reason in-house staff does this work is that one union or another will run an independant out of the building. It's the same for a lot of institutions; the in-house staff says the carpet is uncleanable, the mill wants us to come in and prove the carpet can be cleaned, we clean it, the mill is off the hook, the in-house staff is afraid they'll lose their jobs and then threaten to shut the place down if outside contractors are hired. The building management decides to take the easy way out and accept crappy workmanship.