WILMINGTON, Del.--(BUSINESS WIRE)--Millennials are more likely than their older counterparts to travel with a purpose as 84 percent of millennials say they would travel abroad to participate in volunteer activities, according to a new survey released today by Marriott Rewards Credit Card. Furthermore, 32 percent of millennials are interested in taking a charitable trip, while only two in ten Generation X travelers (18 percent) and baby boomers (17 percent) are interested in doing the same. Conv