The ergodox is still sorta a niche keyboard. Yes, I'm typing on one now, using a mix of five keysets to get enough 1.5x keys but not that many people have one, compared to how many have a keyboard. Also, "custom keycap sets" is a bit of a niche. And there isn't a firm overlap between the two camps, so of all the small-thousands of kits Massdrop has sold, I imagine 90% of those who've assembled their kits just use the blanks they got with them, thinking they were tempting fate enough to get a weird keyboard.
Getting weird keycaps on your weird keyboard? That's ... weird.
Also, welcome to GH. Hang on to your wallet. Or get some aspirin, y'know, whichever.