The real place for the EI is in things like "web enabled thermostats". Such gizmos already exist, and often have poor interfaces. Selling it with an EI socket should reduce the initial purchase cost, and if someone wants to web-enable their purchase then they buy an EI and insert it. If not, they don't. Easier for the manufacturer, easy for the end-user.

Perfect application for it.
I wonder what other situations have as good a fit, though?

I mean, who the heck would want internet access in, say, a TV, Radio, Phone, or home alarm system? Just hard to imagine until somebody does it and others pile cool stuff on top.

Cheers