Yes, it is ego. I was recently on a backpacking trip with a few of the most 'geared up' people I've ever met, sporting all top of the line gear and very proud of it - every single item was intentional and brand names and the long technical details of every item of clothing or gear was always mentioned. It's like almost any hobby or sport - some people will geek out and get very into the 'scene'. Walmart will provide a way for new people to dip a toe into the world of backcountry gear and some of those people will move up to the specialty brands.
It's the history behind the brand that's important.
Does that company have a history of building quality products? Do they support them when something breaks? What kind of reputation do they have?
When you buy a brand name product, you generally have a better idea what you're buying.
(Not to say there aren't some high quality generic products out there, but it takes a lot more time and research to find them. And sometimes it's just a gamble.)
No, but if they see that brand protecting the head of all the people they see eat shit in GoPro videos, or on heads in the Winter Olympics, then they don't (feel they) have to do the research to see if it's a trustworthy brand.
Obviously, this implied value gets taken too far on both sides.