It is a shame but it does sound like you are wasting your time, why do people even bother joining if they don't even move. Its a weird cyber-culture we live in with someone talking to a volunteer like that.
I have never greeted but it was great to have someone play a game of chess with me when i started on chess.com.
Am I wasting my time? I volunteered for the greeter program not too long ago. I stated that I can take 10 new people at a time. As each person starts a game I "greet" each with a note in the chat bar saying "Hello!! If you have any questions please ask." I even sent a PM to most saying the same.
My accomplishments!! At least 25 people have started, no one got past move 4 before they quit. Most do not even get to move 1. Only one used the chat bar, made a move and then posted "When are you going to f...ing move". And that was about 3 min after he made move 1 as White.
What else can I do or am I wasting my time?
Chuck