Typically with free WiFi at establishments (across the country and not just at Starbucks) asking if an email address is not only a marketing ploy, but also determine whether or not your legit or not.
Wow, I did not know this! It might be that you call their offices or speak with the manager at the store when next you visit.
I didn't know they did this. Next time your in the store, I would speak with the manager.
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