When for some ungodly reason Mario Kart 8 Deluxe keeps selling, it can't be reverse racism. If Nintendo players are buying third party games, they're also buying first party games, therefore there's no discrimination here whatsoever. There can't be a preferential treatment for third parties when a Nintendo port from 2015 is top-selling.
Though to be fair the way you actually worded the question doesn't have anything to do with reverse racism, so I guess you just wanted a bit more of buzz for the thread with a not-so-sensible title/opening. Adressing the question itself, they probably do. One reason for this is because third party games tend to have the worst and the best of the industry, so no point ignoring it altogether but rather dwelling into them to see what you can find.