You obviously have not used any remote monitoring tools.
Just to pick one, look at kaseya. Unless everything on the network is locked down, it is going to find a way to connect to the server. Heck, by default it gives you a half dozen ways of remote viewing (mstsc, vnc,..) without manually installing anything beyond the small client package. It's very good software from a management perspective, but using it in a moderate size and diverse environment, it's border-line malicious.
"The Avis WIZARD decides if you get to drive a car. Your head won't touch the pillow of a Sheraton unless their computer says it's okay." -- Arthur Miller