Yes they do. I've seen the "No Outside Food or Drinks Allowed" many times at the EWR UC next to the Starbucks (and also at IAH). And after I was told once I couldn't get in until I finished my coffee, I've been sneaking my lattes in ever since. Next time I won't to see if anything has changed.

Nonetheless, while I understand concerns about outside food, what's the reason behind restricting outside drinks? It can't possibly be about stinking up the place? BTW, I searched the older threads and didn't find an answer.