I think it's people who struggle to find purpose with their lives, that stumble across the truth, or care about the state of things bigger than you like national and international politics. They don't seek it out intentionally, but find it along the way. The ones that are always busy generally have a purpose of sorts in their careers or family, and feel no need to seek out anything else. I didn't pay any attention to politics while I was a student, because I had my goal of finishing my degree, getting a job and finally having enough cash to start enjoying my life. It wasn't until I'd gotten that job, realised it was all an illusion, a promise, and a false hope, that I started looking for something greater.