I can say from experience, my sister was having a last minute, thrown together wedding and was tossing around the idea of having guests pay for their dinner. It was a local wedding, no travel expenses for the majority. Honestly, it was a big blow up in our family over the audacity of her decision lol. I know that in her situation, my suggestion to her was to just have cocktails and appetizers, skip a dinner and save the cost. No one is offended that way. Every family is different, but having the guests pay for their dinner is a little untraditional and will most definitely create some miffed family.