Because advertising works.
I tried to contact a lady a couple of evenings ago, just after her profile appeared in my area.
She messaged me back to say that she was still travelling but that she would be available from 6pm to 10pm.
It was about 20 minutes later before I replied as I was driving.
At that stage her evening was fully booked with 3 appointments.
She agreed to contact me if she had a cancellation or no show but it didn't happen.