Where I vote, if you couldn't vote that day, you don't get to vote. So, yeah, I'd prefer to be able to vote than eat for that particular day, given that the consequences can be so vastly different (someone manipulating the voting system to win, and then execute their damaging agenda vs being kind of uncomfortable for one evening).

Credit cards are a convenience, voting is both a privilege and (in most western countries) a right. They're not really comparable in their importance.

You also ignore the biggest problem: voter fraud. It's so much easier to mess with the vote with electronic voting than it is with paper ballots. Technical people don't like electronic voting, because they understand this. There's no way to be sure no-one's manipulating a voting machine. You'd need to physically interfere with each single person and their single paper ballot with paper voting. That's way harder to pull off.