Some people might frown upon it, thinking, "You should want to do those things without needing some kind of reward system." To those people I say: It's okay to feel good that you called your grandma and also that you earned some points. Think of them as karma points. It seems LESS selfish to me to have some kind of reward system to motivate you than to not do it at all. Maybe it's a "ends justifies the means" thing, but I'm not a big fan on that philosophy normally. However, in the end, you might really start enjoying calling grandma, and heaven knows her world will be a much happier place.
Anyway, props to lifehacker and Mr. Alexander Kalamaroff. Check the article out!