Sadly, the price has dropped now, but this comparison is a good evidence of bitcoin's unstoppable and rapid growth. It reflects how much attention people are paying for it and how surprisingly successful bitcoin has become. Like 7 years ago, who would ever think there does exist a day when an ounce of gold can be bought with just one bitcoin. That bitcoin has gained what gold has right now while it's still young is a clear evidence for a potential future.
Most of the first people that bought bitcoins, obviously. If we weed out those people that bought bitcoins because somebody close to them is highly recommending it that it's almost as if they were forced to buy bitcoins, what will be remaining are the true investors. Those true investors are either very lucky people that have stumbled upon a good article about bitcoins and believed in it right away or people that knew what was going on. It's not like the existence of bitcoin was kept secret. If you were already a trader at that time, you'd know about bitcoins since somebody in your circle of friends surely had the time to look at the incoming trends.
So yeah, those people believed in bitcoins and some of them are probably still holding tons of bitcoins. It didn't cost that much back then so holding tons of bitcoins isn't that big of a deal.