My Dad does not approve of gaming as a hobby. That is about understatement of the year, but I'll leave it at that. He also disapproves of my religious beliefs and uses them as an excuse to punish my gaming.
Just reading this, and I'm thinking that if you ever want to justify computer gaming as a hobby, you should mention the story of William A. Higinbotham. A nuclear physicist who had worked on the Manhattan Project, Higinbotham was a strong supporter of nuclear non-proliferation. In 1958, when he was 48 years old and working as Head of the Instrumentation Division at Brookhaven National Laboratory, he designed one of the first ever video games, Tennis for Two, using an oscilloscope and some analogue components.
This was a man who held the power of the atom in his hands, one that said, in a sense, "We have this almighty power in our hands. Let us use it to transform the earth, not turn it into dust." If this man could see the merits of video gaming, I don't think there's any need to be ashamed of it.