Visiting Las Vegas and Phoenix (from NZ)... any recommendations of nice wee outdoor gear retailers I should try visit?

Emphasis on shops that stock ultralight gear or cottage industry gear and clothing. I'm not really looking for anything in particular (though I have a couple of items in mind such as dyneema stuff bags, or coffee makers), but keen to have a browse and see if anything catches my eye.

I'm only visiting the US for a week and a bit, and ordering online isn't really an option, plus online is not really the point.

Maybe REI is my only real option for outdoor gear, but I'm not from the US so I have no real clue if such places exist like they do in some places in New Zealand. Just thought I'd check so I don't miss out on any gold mines.