The difference is that commercial VPNs are theoretically more beholden to regulatory bodies to shutdown bad traffic/provide subscriber information when so ordered by a court. With a commercial VPN you have a legal recourse against a bad actor. With residential proxies enforcement is much much harder, as traversing beyond the IP hosting the proxy to the TA is often not possible. I also use a VPN to get around content restrictions and have no qualms about their use. Residential proxies are typically bad for everyone except TAs and people who might not have access to traditional VPNs due to their local governments.