Friends and camping

So my husband and I planned a camping trip with some friends. We asked everyone involved how serious they were before we booked a big cabin. Since then one family backed out because, they think they have to work and another couple went from going to not going to going to possibly not going again. I don't want to ruin friendships over money for this damn cabin but these friends committed. Should we still ask for money? Btw, never doing this again.