Cravings can happen for any reason. There is some evidence to suggest that our bodies use cravings to tell us about nutrients we are short of. You might be missing potassium, or feeling a bit anemic which would lead to a burger craving. If you’re feeling low on energy then craving carbs is a way of your body encouraging you to top up fast.
Then there are the pregnancy cravings (tinned grapefruit in my case) which I don’t think make any sense! That can’t be the explanation for this heartfelt cry overheard by Alex 3000, though. The guy clearly needs Sour Patch Kids desperately, so who are we to question why? Just get the guy his candy!