Now millennials can add “bad tippers” to the roster of negative stereotypes they’re associated with. According to a new study from creditcards.com, 10% of millennials do not tip at all when eating out. In contrast, only 3% of the older generations don’t tip. Even when millennials do tip, the study found that the median gratuity is just 15%. This is under the national average, and significantly less than Gen-X, baby boomers, and the ‘Silent Generation,’ all of whom leave a median tip of between 18 and 20%. The same attitude applies to tipping those who provide services, such as Uber...