Just wondering what everyone is doing to feed evening guests? Some places...

Just wondering what everyone is doing to feed evening guests? Some places we’ve looked at have recommended only to cater for 80% total of evening guests whereas our leading venue says to do it for 100% so not sure what’s best. I would absolutely hate for there not to be enough food for everybody but on the same note don’t want to pay unnecessarily and have loads go to waste! Any advice on what your all doing or how it’s worked out for you on the day ? Thanks x