I've seen a couple of minor accidents myself and I don't really like fireworks that just blow up and\or without a fuse. I don't trust their producers in the price range that's usually affordable to my peers. That thing being completely delegated to pros with expertise (and a full set of limbs) isn't bad at all, and they usually do pyrotechnics when and where hundreds of people can si,ultaniously enjoy them, unlike a fingerbomb one can ignite on the street.
It can also be context-specific. Sometimes the L can stand for "Lunch", for videos you shouldn't watch while eating or might otherwise trigger a gag reflex (gore, pimple popping, anything with creepy crawlies, etc).