That sucks. It makes responsible disclosure seem marginally less attractive without any type of reward. I am sure most people would either do it or not, but there's probably some on the fence. And some people might actually start looking knowing there was a legitimate reward.
There's a bit of back and forth between intrinsic and extrinsic motivation, where an external reward can reduce intrinsic motivation more than it increases extrinsic motivation. That is, if the reward is known but small, someone could go form, "I'll submit this since I want to help them out," to, "I'm not going to work for below minimum wage!"