What should i do about post-prom after party?

Ok me an my friends all decided to go prom with our dates(couples). We rented a limo and everything but then we all came to a undecided agreements for what to do after prom. We already payed for the limo an everything. Majority of us want to go on a boat cruise after prom for a really good price for $50 an that includes full buffet, DJ, and a free picture on the deck with your date for 2 hours 12:30am-3am. Well only 2 couples out of 8 of us total said they just wanna walk around but I been planning this and its not fair. I did everything I could to try to make this night possible. I'm so upset. Idk what to do. Please help me. An also the limo wont have us at two places at two different times. I can't give them there money back for the limo. But I hate they change there mind at the last minute.