Another vote for "never buy white socks". If you're not able to get the stains off, I personally am too cheap to throw away something because of stains. I'd just wear them until they broke out in big holes.
When I got my first serious road bike, it came with white handlebar tape and the sales guy thought that was very much in style. Then, got white cycling shoes ... I will never do that again. Black or some other color dark enough to hide the problem in socks, shoes, handlebar tape, etc etc