A friend of mine is heading there next week and is not sure if he should bring some extra shoes or not. I have never been hiking in Vegas so I have no experience with Red Rock. Does anyone here know?
From what I know (I have never been but know a few people who have gone) regular walking shoes are enough unless you plan on going off-trail. So whatever shoes you can comfortably walk in is good enough!
You don't need anything special. Just whatever he decides to wear, tell him to make sure they are comfortable for him. I would wear older beat-around shoes too just in case it is a bit on the messier side.
I would wear boots to protect your feet from the snakes and venomous spiders and scorpions. If you happen to be walking by one, you don't want to be wearing something they can bite or string through.