Back at my store, Bayo was dropping in price rather rapidly. I didn't see DmC hit the $30 mark for about a yearish. Keep in mind, these are new prices, and those are set by the publishers, so Sega could have already been jumping ship on it :/ However, these games also debuted in a time when used game sales became more and more prevalent, and DmC had a PC release, which means downloading it was always an option too. There's a lot of factors that completely jigger sales numbers.
I always say though, that Stylish Action Games never have incredible out-of-the-gate sales, they always trickle in because more people see how awesome they are through word-of-mouth and combo videos.
But then again, sales aren't indicative of quality anyway, so bleeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeh~