Millennials --- the roughly 79 million Americans between the ages of 16 and 34 --- favor brands that have Facebook pages and mobile websites; millennials are more likely to shop for groceries at convenience stores than middle-age folks, and they are more receptive to cause marketing campaigns. Those are some of the findings from a new survey conducted by the Boston Consulting Group, the marketing services firm Barkley, and Service Management Group. As for the perception that millennials are lazy consumers, that’s way off base.