> Why all the hate? It's not like you have to use these everywhere just because they exist.
I do, because I can guarantee that some self-proclaimed web designer will use them for absolutely no reason at all.
> The fact that it's possible is good to know as one day it might be a good solution for a problem I'm facing, and then I'll be happy that it exists.
This argument is so useless. "Well maybe someone wants to shoot themselves in the foot. Nobody can come up with any examples, but maybe."
> Attracting attention to options in a demo
None of the effects are really useful for that. Apart from them being too wacky ("did something break?"), anything transitive is bad for that anyway, because what if the user gets distracted for the split-second your animation runs? Fade in some persistent element for that.
> If we restricted web browsers to what developers think we should use, we'd still be using plain green text on black terminals.
Command-line tools are popular for a reason: They get shit done, and don't distract people with useless crap.