Therapists generally do need to set some parameters around contact, and it seems that many have found ways to individualize those parameters. While the vast majority of clients use that contact with respect for the therapists' time and life, there is that minority who would abuse the privilege resulting in additional stress for themselves.

I've seen right here on PC posters who spoke of spamming their therapist with literally dozens of texts or emails in a day. Full outside contact clearly wasn't working to help the client nor the therapeutic relationship which inevitably became highly strained. These instances are probably fairly unusual, but they demonstrate that therapists do have to have some reasonable parameters they work within and the ability to individualize them for clients as they learn more about them.