Yes, it is really okay. The usual protocol is too not be ostentatious with
them (i.e. I wouldn't start jumping up and down and yelling I have strategy
cards!!!":)) but since most casinos SELL strategy cards in their gift shops,
they really can't have a problem with it. Your strategy cards are just better
that the ones they sell.
I use and have used strategy cards at many casinos, as do my friends, and no
one has ever had a problem, and we don't hide the cards (then it would feel
like I was doing something wrong).
Have fun and good luck
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