Things I don't understand

I was getting a burrito this morning and a [vegan?] lady ordered a decaffe soy latte. Now what the fuck is the point of that?

I can understand ordering a decaffe latte because you like the taste of a latte but don't want the caffeine. I can understand ordering a soy caffinated latte because you want caffeine but don't want to drink milk. But what the hell is a decaffe soy latte? You don't want caffeine but you want a drink that tastes like hot cat shit?