Putting Ace's face on a face from a gambling movie or putting his face on money, or putting his face on some guys head behind a big pile of money, isnt funny to me. Because thats what he does, he's a gambler. He already has pictures with money, and pictures in gambling settings. So why continue to take his face and put it in a situation he already engages in anyway - such as gambling.
It would be like putting Carl Lewis' head on some pole vaulters body. It's sort of what he does (track and field) and it just isnt funny because the picture is realistic. The picture becomes funny when its outrageous.
It's funny when you take his face and put it in a familiar everyday situation that has absolutely nothing to do with the original picture or gambling, and take his face out of context of the original picture (gambling and money) and put it on a picture that it was totally unintended for.
Hope that makes sense.