Don't know why you're surprised at this, it's the same in any service industry. Escorts, bar staff, waiters, waitresses, garage owners etc will all be nice to the customers face, doesn't mean they don't slag them off behind their backs or even like them.
They are all getting paid to provide a service and the better the service they provide the more custom they get.
The only person I can think of who was honest about what he provided was Gerald Ratner and that went well.