Oh, I didn't mean to put your comment into question. I did find pictures on the internet like these, so it seems to be a thing:

Purple carrots have been around for longer than the orange variety, though, so it'd be a bit weird to create a variety which is only purple on the outside just for scam purposes. Like, you can likely get the seeds for actually purple carrots much more easily. 🙃

From what I understand, this is what carrots often looked like originally. It was later on that we selected for more orange carrots.

Either way, they certainly don't taste beetroot-y. I've heard them described as somewhat sweeter. I've had them only once so far, but would agree with that description in the sense that they have a more rounded taste. I think, I like their taste slightly more.
Wikipedia also says that the orange carrots probably won out not for tasting better, but rather because they don't discolor stews, which is a fair reason.