Residential IP addresses tend to have better reputations than datacenter networks, so there are providers who sell access to home internet connections. Oftentimes the people running the proxies have no idea they're running on their network, they're quasi malicious.
https://cloud.google.com/blog/topics/threat-intelligence/goo...
"Quasi" malicious? What's quasi about it? It sounds completely malicious and fraudulent to do this without the knowledge of the network owner.