I wore wedges for my wedding, and switched to flats for our reception. I think walking in heels on the sand would be very difficult. They do rake it down fairly nicely for events, but it's still sand and it'll shift on you. And it probably depends on which gazebo you choose too - some are closer to the sidewalk, so less walking in the sand than others. The gazebos that are in the Casitas section are closest to the sidewalk. The presidential gazebo, white gazebo, chapel terrace gazebo and gazebo 55 are a little further. If you are using the Mexican Gazebo or the Chapel itself, it'll be just fine as those approaches are all sidewalks.