Quick answer: Starcraft 2 doesn't have LAN.

Long answer: Good luck playing in Starbucks. Good luck bringing and using your desktop (or desktop replacement) on the small, cramped tables in Starbucks. Good luck negotiating with the bandwidth when you have countless other people using their mobile devices within the Starbucks network. And even in the event that the internet is ok for you to play in Starbucks, WHY would you even think about playing there?