Years ago, the first time I went to Emerald Island and asked for blanks I was almost thrown out of the casino. They actually had security called and asked me to leave. Fast forward to two years ago after the last convention when I stopped there the player reward manager knew who I was and spent a lot of time with me and introduced me to the owners, plus gave me samples of all their cards. I went back this year after the convention and when I asked again for blank cards I was told flat out NO. I asked to speak with the manager and guess who walks out.... the same manager I met 2 years before and she remembered who I was plus gave me samples of all the cards again.
As for other casinos, most will NOT give out blanks any more for one reason or another. I did manage to get a few after I mentioned I'm working with the MOGH and doing the guides. Some times it's just a matter of who you meet at the counter, one agent will help and another won't. What I never understand is why the casinos are so possessive of their cards and don't grasp the marketing opportunity of giving out a few cards to collectors.