Songs from film soundtracks make little impression on the charts nowadays. Take That's Love Love which featured on X Men: First Class being an example. Weezer have covered The Cars 1984 American hit You Might Think for Cars 2 which is currently getting bad reviews in the USA. It's a pure carbon copy of the original and doesn't seem to be a single. The Cars have a new album, Move Like This, out at the moment so why not just put their original song on the soundtrack? Because the kids have never heard of The Cars of course.
Here's The Cars and their number 8 Billboard Hot 100 hit song from 1984. It got to number 88 in the UK.