No, nothing important! :p

They're just versatile:

- they stack and interlock,

- tools and supplies stored in them are nicely visible,

- if friends crowd in you can sit on crates as improvised stools,

- you can stand on them to reach high shelves,

- you can put a board over and between two as an improvised additional workbench.

- I have grown mushrooms in them (fungi can't eat them and they're easy to clean).

And if I somehow manage to break one, I'm out of pocket like a couple of dollars :-p