It's not so exotic. The ones I knew were plumbers, landscapers, car detailers, etc. and maybe they weren't millionaires (maybe). Worse, the friggin landscapers would hire my good part timers to work outside all day and then they were too tired to come in on the preload or night sort the next day.
And then when I helped deploy preload smartscan (version 1) out in North Cal you'd be surprised how many preloaders were telling me everything I did wrong, when I asked how they knew what they knew, the answer would be, oh, I started a business out here in Silicon Valley and sold it to HP 3 years ago. I just do this to get out of the house and protect my nest egg with health insurance.
It's not all 19 year old kids blazing weed in their mom's car in the pk lot 10 min before start time.