Honey, you are looking at only federal pursuits, which the odds of finding those is probably a billion in 1. And someone has to sit down and check the rolls against voters that appear to be able to even find a suspected fraud, which most election offices simply do not have the time or wherewithal to do. And you know that.
Many of the ones found are by groups or media taking the time to check those rolls, and then they get charged locally or through the state.
And unlike you, I don't want my vote washed out by one single fraudulent vote.
Voter fraud is like speeders on the highway. People are driving 15, 20, 30 miles over the speed limit. But if there are no police officers to take laser and catch the speeders, there are no speeders as far as the authorities are concerned. Anybody can speed because nobody is there to stop them.
Voter ID is that police officer taking laser. It's there to slow motorists down and hopefully stop speeding from taking place. If strong enough, deter people from speeding in the first place.