I don't agree, it's just one day in a year and as long as they don't take it overboard I find it a great laugh.
Besides if you're that annoyed by the email just send it to trash, it only takes a second.
Except for the one day a year bit, which is key. In fact, to all spammers: you can send me all the spam you want before noon on April 1, if you in turn agree to not send me any spam any other day of the year.