On March 17, from 3 pm to 7 pm local time, participating Baskin-Robbins locations will offer Mint Chip 'n Oreo Cookies Milkshake samples for free in celebration of St. Patrick's Day. In addition, it offers a regular scoop for free when you download the Baskin-Robbins mobile app. That's a savings of about $3. Click here to find your nearest location.