Why do people who are trying to lose weight drink sugary energy drinks before a workout?

I know you're probably thinking 'well duh, for energy' but if there trying to lose weight and they drink something full of sugar and glucose which is almost 200 calories, they wouldn't be burning off as much as they could if they didn't consume those calories, wouldn't it take longer for them to lose weight in the long run? Am i making sense? Isn't it just best if they stick to water? Nice answers only please. Thank you =)