Some people use it by dropping files up to share with people, and don't use the syncing capabilities. It's a reasonably common use case, I've noticed.

Some people also use it like a USB dongle, and drop files up manually, then download them on computers they don't have installation privileges on.

I use it to sync the pictures and videos from my phone, which is then synced to my desktop at home, and then deleted from dropbox and thus also the phone. Automatically. If my phone gets stolen (or data deleted by some overzealous border patrol goon) it doesn't matter as much as it would have otherwise.

I do, because all the people at my office using the desktop app complain about bad syncs, sudden filling up of the local hard drive and general slowness

Sarcasm is hard. Unless I'm mistaken, you're imitating Blizzard and Diablo Immortal. If not then I think your comment comes across as extremely blind to a large segment of users.

I was forced to use web interface after app reinstall because Dropbox free account now supports only 3 linked devices (and I have 7).