It's pencil in Canada too. Pencil works. Ink pens stop working, and are far more expensive than pencil in bulk. Voting is old. Using fountain pens, and quil

It's pencil in Canada too. Pencil works. Ink pens stop working, and are far more expensive than pencil in bulk. Voting is old. Using fountain pens, and quills to vote, is far more annoying than pencil when it just works. The mark of vote being indelible or not is irrelevant. The monitoring and protection of the ballots is far more important. For example, representatives of all political parties are involved in the count, oversight by an agency, etc. If you had time to erase and re-mark ballots, you could swap out paper ballets too.