With respect to mail-in voting, I have group of five family members who share your sentiments: that it is all a fraud and shouldn't be allowed. All but one of them voted by mail. They cited convenience of researching candidates and issues as they read through the ballot, convenience in avoiding crowds, and convenience in reducing transit time. (I can't recall if the other one did early in-person voting or in person on election day).
Point being, they were arguing it's a fraudulent system, but participating in the same manner while able to vote in person if they really wanted to.