Starbucks will give you a free coffee if you prove you voted for Hillary Clinton!

While your statement is technically true, the information I found on the Internet suggests Starbucks will provide a free coffee to anyone for simply showing that they did vote, regardless for whom they voted for.

http://www.miaminewtimes.com/restaurants/vote-on-election-day-and-get-free-food-and-drinks-correction-appended-8907677

It is, however, also true that Starbucks CEO Howard Schulz endorsed HRC for president.

and they pee in the cup first if you voted for Trump.