The only way I see it going over positively is if a specific charity was chosen before the game and the game was promoted as a way to benefit said charity.
I'd bet, if it was just announced as $1 for admission and it's going to charity you'd find a handful complaining about breaking the tradition of it being free.
I'd rather the event be used to promote a charity, but the option of donating left up to each individual. AND, enough people to handle it. There were a lot of people that planned on donation for the tornado fund a two years ago and couldn't find anywhere to do so.