Programming is not a particularly difficult skill. During the 1980s, it was taught in grade schools. JavaScript may be a worse and more difficult language than the ones you could find in the micros scattered across schools, but it's not an order of magnitude more difficult to use effectively.

In a field that goes hand-in-hand with programming, which includes pretty much every artistic one, it shouldn't be all that surprising that people know how to use/are at least curious enough to learn the tools available to them.