Sometimes they don’t notice that the postage is wrong, or even missing entirely. I’ve heard stories of people drawing “stamps” on letters to see if it would pas

Sometimes they don’t notice that the postage is wrong, or even missing entirely. I’ve heard stories of people drawing “stamps” on letters to see if it would pass, and I know I’ve successfully mailed a letter without putting a stamp on it at all (by accident, and was surprised that it was delivered).