Bachelor party hotel etiquette

[wadea]

So eight of us are staying at Excalibur for two nights for a bachelor party. We’re booked two to a room (say $100/night). I know that some of us plan to play enough poker to score a poker room rate ($75/night). I don’t know for sure who will be playing poker and who won’t. In the case that no poker is played, we would split the $800 tab evenly between the 7 non-bachelors. How do I deal with the following potential problems:
1. Only one person in each room plays poker and all rooms are discounted. The tab is $600. Should the poker players pay a smaller share than non-players? How much?
2. Only two people play poker. Two rooms are discounted. The tab is $700. Now how much does everyone pay?