Nike aren't paying a lot just so they can make profit on the shirt, it's a good advertising opportunity. QPR are likely to get promoted this year or next ,and so Nike will get 3 years of exposure in the Premier League, during matches (on shirts) and after matches (on the advertising board behind interviews). On top of the exposure they get the profits from selling merchandise to sweeten the deal.
You're right because before this I'd never heard of Nike so they must need the exposure!!