@AC Re: It's not "why", it's "how"
Here's the problem... voter fraud exists and it has an impact.
There were some major issues like 100's of ballots being sent to a single house of an old woman.
People who cannot vote, registering to vote and voting. This includes illegal aliens and convicted felons who have lost their right to vote. The issue is that they are being (self policed) which is like saying to a convicted felon... go ahead and vote. The odds are you'll never be caught and if you are... its unlikely you'll serve any jail time...
The larger issue... is automatic voter registration. You get a drivers license, you're eligible and registered to vote. It sounds good, but when you allow illegal aliens or even green card holders to get a drivers license, they are then being registered to vote. (The devil is in the details.)
Sorry, but both sides play games and if you're in Chicago... even the dead can vote. And vote often.