A lot of them are there because they have regrets about a time in their youth when they had the opportunity to become activists and "do something", but let it pass them by. They've latched on to this youth movement as a way to make up for it, in the belief that the young must surely know what needs to be done, because they knew what needed to be done when they were young. Add in ignorance about the actual topic, meaning they take what they're told by younger leaders and authority figures as gospel. They want to finally make a difference before they peg out, maybe even be remembered by future generations.