pinching numbers

Hi everyone, I'm having my wedding in Fort Lauderdale FL April 2010. I'm already concerned about my numbers getting too big because of obviously the cost, and also I love the reception room I picked but it isn't very big and I don't want everyone to be on top of eachother. It's a rotating room on the top of a hotel. Its mostly family and a few close friends, other than my bridal party I was thinking of inviting a few friends from college without dates. Would that be really tacky or is it something I can get away with? Any advice would be helpful!

-Katrina