I don't have a problem not to turn on the computer for half of a day, occasionally (usually when I'm a guest at weekends). That is, as long as I use a cell phone to read e-mail (at lease once per hour).
Well, when you are in this business, you simply don't have a luxury to ignore e-mails. Vacations? Without computer and operating internet connection, it wouldn't be a vacation but a punishment...
Edit: Hm, yes. It seems I found a perfectly valid reason to justify my addiction.