People who buy mythic+ carries to ksm and weekly carries to max out their vault are getting gear sold to them by someone else who “provided” it? In what universe is the vault gear “provided” by someone else who earned it and sold it to you?
A full heroic clear costs 20 tokens, your weekly cap. People who want to spend that much weekly PLUS mythic+ are just going to find someone to take their cash. And they will find them.