I've sometimes bid lower on chips that had a high reserve ... and have on occassion been contacted by the seller after the chip didn't sell ... and was asked if I wanted the chip at my bid?

Some folks are just testing the waters .... or they think that their chip is worth more than it actually is. It doesn't hurt to put in a lower bid than the reserve. It demonstrates that you are interested in the chip and the seller can make up his/her mind whether to accept your low bid or not.