It doesn't bother me if people say they pray for me. What they do with their time is their own business.
I think prayer can be good for people who pray in the sense that it gives them peace of mind. But as far as prayer working, I believe it is about the same as wishing on a star or crossing your fingers. All three work an average of 50% of the time.
Unless of course, you're praying for snow and then it's clear that God loves northerners best.