I sell pottery, so my display would be different than for soft fabric things. I've seen grid walls with hangers or makeshift clothes lines to show off fabric items.
Putting up wall is a personal choice. If it is windy, maybe not or if the booth next to your is ugly or distracting, maybe yes. I just have the sides that came with my EZ up which aren't very attractive so I usually don't use them, but if a multi-day show, I do put them up at the end of the day to hide/protect the contents.