The Bitcoin Address Generator page is mainly for developers, programmers, and others that want to double check their Bitcoin Math. The page clearly warns users NOT TO ENTER PERSONAL Private Keys.
Having said that, I am also working on a downloadable version, open source, for use by public interested in generating addresses OFF-LINE.
You should appreciate the beauty in this brand new technology!
I don't see any market need for another random key generator. However, as you say, it is a good check on maths/other generators.
It is also attractive to ppl who have affinity for cards.
The process does have a new market for online casinos and online poker sites. Each hand is published in the ClearShuffle Blockchain before it is dealt to players. This assures players that the deck was not tampered with before or during the hand. See the home page at ClearShuffle.