No.

It would put crew in a completely untenable position. While consumption of alcohol on board is certainly permitted, excessive consumption is not, and it is down to the FA's to enforce that. By permitting a game of beer pong to begin, FAs then lose the ability to exercise control over the drinking if it gets out of hand. Given reduced partial pressure of oxygen and reduced humidity, the intoxicating effects of alcohol are going to be enhanced, increasing the likelihood that drinking could get out of hand.

...and playing flip cup with J class glassware is a bad idea!