Email is still the most intimate way we have to communicate.  It’s personal.  Even if we resent the spam, we still click on it if the subject matter scratches the itch of the day.  Everyone hates spam about flooring until that day when they just happen to be looking for the right flooring option for their new house.  Very few of us intend to start our business day by shopping for shoes but the right message can bounce our attention into the world of fashion for the better part of our morning.  We just can’t help it.  We’re human and we have to click.