Are card games proper nouns? Should they be capitalized?

My own inclination is to answer "yes" and "yes," respectively.

However, some sources which I respect and consider at least somewhat authoritative do not seem to capitalize the names of some card games, in particular "bridge" or "poker." (Interestingly, the card games cheap prescription drugs without prescription "Hearts" and "Spades" seem to be capitalized more often, perhaps to differentiate them from the suits after which they are named.)

So, two questions:
1. Are the names of card games proper nouns? (I think the answer to this question is almost certainly yes.)
2. Should the names of card games be capitalized? Does this depend on the game?

I would prefer to award best answer to an authoritative answer (i.e. you should provide some reason why I should believe you over the average person, such as you have an English degree, or you are a journalist, or you have cited a grammar or style reference which mentions card games specifically).

Thanks for your help in advance.
However, please do not let my preference dissuade you from answering; I am interested in what you have to say.