Hmm well there's no folders but if you interact with the object the URL does become nested. So in a sense it does behave exactly like a folder for all intents and purposes when dealing with it that way. It depends what API you use I guess.

I use S3 just as a web bucket of files (I know it's not the best way to do that but it's what I could easily obtain through our company's processes). But in this case it makes a lot of sense though I try to avoid making folders. But other people using the same hosting do use them.