Well it makes sense now. The PSP remake has been around for years and is out of print. The only copies I've seen in stores recently are those in the clearance sections for under $20.
The reason we haven't gotten the VC version yet is because Konami wanted to milk the sales of the PSP game as long as they could since the whole selling point of the PSP game was it's the first time Rondo was released out of Japan. Well now that that cow is bone dry, there's no more point in not bringing the original game on the VC over since it'll just make them more money and not eat the remakes sales.
It's similar to how it took so long for the classic Megaman games on the Virtual Console to finally come to North America even though they were out in Japan and Europe early on. Since Megaman Anniversary Collection was only released in North America, Capcom wanted to milk it's sales here as long as possible. But since it wasn't around in Europe/Japan, they had no problem releasing the early games right away since there was no sales for it too hurt.