> Why?

For a non-trivial amount of ballots, the overhead of securely managing the ballots is substantial. You're casually driving up staffing costs all over the place, and legal challenges will ensue if everything is less than meticulous.

To your point, though, Virginia blows a great deal of money on elections. Check out all 19" of our local glory: https://www.fairfaxcounty.gov/elections/sites/elections/file...