Nobody is gonna pay for a VSCode theme.
People are willing to pay for nice things. Especially if it takes longer to create it yourself.
A theme is more than a list of colors. Monokai Pro contains custom designed icons and color filters too, and some code logic to sync it all up. It needs continued updates, as editors keep evolving with new UX/UI elements.
Free themes are a dime a dozen.
Paid themes means someone's incentivized to keep working on it and adding icons, &c.
Assuming that the editor never removes/adds/changes anything then yeah, it's basically free. But since most editors are somewhat of a moving target, it does take a bit of maintenance to make sure everything continues to look right as things update.
The worst part with maintaining a theme/colorscheme is that you can't really rely on automated testing to catch most of the issues, unless you start doing snapshot testing comparing PNGs or similar, and is the biggest time-sink when a new editor version been released.
I am more curious as to why one would buy the theme and related merch.
You can even prepare ringtones on your phone with the iOS version of GarageBand.
Yeah, so only-iPhone users are out of luck since the majority of people don't have a Mac. Last time I used Android you needed the file and the phone itself, you select the audio file and you're done.
I'm comfortable working without any syntax highlighting at all. It's not that I go to the effort of turning it off, I just don't really care that it's there. I used to use Sam as my daily editor - got used to plain black text pretty quick. It's all a matter of preference.
I suck at colors and want nice themes. I'm glad people better at this than me take time to make nice things.
But, I don't want to ever manage licenses for my theme. My dotfiles need to fetch it automatically or it's out.