A better way of doing this is having the hidden form element named 'email' and the actual email input named something else, as many scripts will be set to auto input based on these submissions
Also, if you do that you need to remember to keep track that the email variable is actually a honey-pot and whatever name you choose is the actual e-mail address.
Of course, a determined spammer will overcome these hurdles. But most spam bots don't bother.