Just because adults are older than children, doesn't mean they're more mature. If you want proof, I urge you to go work a few shifts in customer service or drop in on a local nursing home's weekly Bingo tournament. Adults throw just as many tantrums as children do, and sometimes in worse ways. 

One EMT described responding to a call of a heart attack in a donut store. Only, the woman was pretending. After being informed that her favorite flavor was unavailable, she threw herself to the ground and wailed in frustration. When the police were called, she claimed she was having a heart attack. 

Read about her, and many other adults embarrassing themselves with their tempers.