I am a lawyer and when I practiced full time, people would call me at non-regular office hour times. That is fine with me because I billed for that time.
For whatever reason, I personally blame the medical model, therapists don't just build it into their K that they bill for time (other than scheduling or short technical stuff). I think that would go far in solving a lot of this. I do not believe it is because they can't "do therapy" in email or phone calls.