I can think of some situations where wifi would actually be an undesirable thing -- I'm thinking of ones where privacy considerations are very big.
Those folks may or may not be the majority, of course.
Personally, if it will do the stuff I need it to, the better visibility of the e-ink, and the greater battery life that goes with it would more than off-set the lack of "laptop" features. But I'm not looking for a fully stand-alone device in the first place, but rather a data appliance.