Well . . .
I would disagree that it will always draw attention. Example, I play poker in addition to BJ. Its very popular for poker players, myself included, to wear sunglasses during play and as part of your "persona" around the poker room. If you're in a casino that's known for its poker (like Binions) and play the BJ tables with sunglasses, some PBs may not give you a second glance. Of course, it helps if you've been seen around the poker room, but you can also use it as cover, as in, "I'm just stopping to play some BJ while I wait for my name to be called for 10/20 hold 'em".
BTW, 10/20 is somewhat of a high-level game so don't use this exact line at a $5 BJ table :-).