You know. It is somewhat similar to people with different sexual orientation. The whole coming out thing, it's not easy for many.
The stigma of gaming is still strong, especially in some parts of our wonderful world. When you say openly "Hey i play video games" people tend to go "Uh whaat? Ain't those, like for, you know, uh, like kids, like?". Some time will have to pass, till the older generation that got unlucky enough to fully ignore the whole computer-world expanding onto their lives, will either accept the fact or die from natural causes (yeah... natural, right).
I personally never shied away from it, even my office has gaming posters and gaming references all over the place, but it took time to convince some of my bosses and co-workers that it's not some idiotic toy for little kids.
Surprisingly they had much easier time accepting my music and clothing style (mostly something you could call cyber-gothic/punk/classic gothic) than my gaming hobby. For them internet is just a tool for work, checking the news, contacting with business partners and so on. They maybe played Solitaire once or twice, but never bothered with anything more. It is the harsh reality.
Just like you cannot force people to be fully open everywhere about their religious beliefs, sexual orientation or other private details, you can't expect them to not want to share their, still often frowned upon, hobby.
Gaming as a wide spread phenomena just surfaced really not long ago, 6 maybe 10 years ago. You need at least another 5-10 years for it to become socially acceptable. Believe it or not, not everyone lives in US.