We had the same thought... how can they charge us for a reception when my guests have already paid for an "all inclusive" resort? However, we did decide to go with the private reception, and I feel certain we will be happy with our choice. Much to our surprise and excitement, we have about 50 guests coming to the wedding

So to us, it's worth it to know that our guests can all be together at one time and place to celebrate with us. And even at $75 a person for the private reception... we are still paying a lot less than we would have for a hometown wedding in either Raleigh, NC or Atlanta, GA.
We are working to keep our costs as low as possible in every other area, so if you have any suggestions... please pass them along.