I've commented on the benefits of wide angle before, but perhaps an actual photo might make a better point...
I took this picture standing at the very edge of the corner of the room, not able to back up any further, and was barely able to squeeze everyone into the picture. This was with my 28mm camera. That means none of the standard 35mm cameras would have been able to get everyone in the shot, while it would have been much easier if my camera was 25mm.





