I tried to do a walkin one evening at Trails End (we were staying at WL). I took the boat over only to find the wait 1-2 hours. YIKES. I could've stopped at the desk at WL and made an ADR, or have known about the wait, but I didn't, and had to come back and eat in the food court at WL. This was early Feb and a slower time then during September and
free dining. We were use to just walking in to TE so didn't think we needed an ADR. So I always suggest making one, even if you do it before heading over because it can be a pain getting there only to find no room at the Inn for your family. Better safe than sorry (and hungry).