I think that is pretty reasonable, considering the number of days that the reunion will take place. Some are going to complain no matter what. You are right. If they want to go they will pay, if they don't want pay they will stay home.
My aunt and I have been doing this for years, each year we try to get new family members to participate. Last year some new one's, (not all) waited until the last minute and were the ones to complained, last to pay and then want to move the reunion and were supposed to plan the reunion for this year, but have not done zilch for the 2013 Reunion. So we gave them until Jan, still no plans, so we trying to do some planning for October 2013 Reunion. Time is of essence. Some plans need to be taken care almost as soon as the previous year's reunion is over. Anyway, we try to be organized people when it comes to planning and I told the other party that. Good luck to all who are planning a reunion this year. Just a little venting on my part.
Thanks for reading my post.