My friend owns 15+ apartment buildings in "not so desirable" neighborhoods. He deals with a lot of tenants who don't pay rent and eventually he has to evict them.
3 months ago he was evicting someone for not paying rent for 12+ months, and a week before the police were going to help get the tenant out of the apartment, his employer stepped in and paid the landlord his back-rent in full.
The tenant was employed at a local roofing company. Apparently he was a good roofer, and the owner of the company didn't want to see the worker homeless, so he stepped in and paid a year of the guy's back rent. (And here's the twist... after his employer stepped in and settled his back rent, the tenant still refuses to pay rent, and will be evicted again 6-9 months from now)
Maybe debt collectors have had similar luck as the landlord in this story, but that's probably a secondary motivation. Primary motivation for the debt collector is intimidation. Debt collection agencies are ruthless in all ways imaginable.