Seriously. Go ahead. ... No? Wait, lemme try something.
How about now? That any better
This is a bit of an extreme example, I admit, (and a joke about as old as the sun) but it illustrates how hard it can be to divine what the hell someone is trying to say when every word in a hashtag or URL is the same case. Want a more mundane example? I just saw on my Twitter feed:
5 yo (v. sad): When I grow up, I want to be boss of the family, but I'm going to be a DADDY, not a MOMMY, so I won't be. #hereallysaidthisIt's very cute, but the punchline got muddled a bit because the first time I read that hashtag my brain deciphered it as "Here Ally Said This." It's a perfectly reasonable sentence - if you throw a comma in the right place - but, in this context, it didn't seem to make much sense. I furled my brown and read it again, finally coming up with "He Really Said This." (Forreals?! No wai!)
Why is this kind of stuff bad? Because it introduces ambiguity; it makes me think. In particular, it makes me think about something that I really shouldn't have to think about. Hell, it's not even something that the person on the other end wants me thinking about. (Ahem... unless you're trying to trick someone. Like I just did. #doasisaynotasido)
Plus, it's a mistake that's laughably easy to avoid. Not that that seems to stop people - apparently there's a whole blog dedicated to this stuff.