It's their store, it's their business, it's their wlan (AP 00:90:4B:24:CF:25). It's their decision.
However, it's *my* money and *my* patronage, and they are about to get a lot less of either.
The Vivace has never been one of those "random social interaction" cafes that the the places that are shutting off their wlan are trying to get back to, even before the spread of wlan. The only groupings who come here are those who come here as groups. Most of the people sitting at the tables are students, hunched over textbooks and doing homework.