...Grumpy Cat?

Look, I'm not a big fan of memes in general. I can't really get into a type of subculture that relies exclusively on variations of someone else's work, especially when the original work wasn't even a joke itself.
But this one specifically is starting to boggle me.
It's a cat with feline dwarfism that causes her to make a stereotypically grumpy face. Okay. The humor of that has a half-life of about 3 seconds. It's kind of cute, but not really the funniest thing I've seen on the internet.
So why the fuck is this,
http://mashable.com/2013/08/05/grumpy-cat-weather-app/
this,
http://www.thewrap.com/media/column-post/hollywoods-rising-media-star-grumpy-cat-sparks-feline-frenzy-kitson-105616
and this
http://search.hottopic.com/clothing/Grumpy-Cat
happening?
I mean, just this weekend at Warped Tour, I saw 3 different fuckers wearing Grumpy Cat T-shirts, and just the thought process of wanting to buy that is turning me for a loop. Are you supporting the artist? As in the guy who bought the deformed cat and whored it out to the Internet? Or is it supposed to spark some sort of conversation? I just don't get it.
Can someone help me out on why this is as big of a deal as the Internet would have me believe?
EDIT: Just as I started browsing after posting, this shit popped up:
http://www.thinkgeek.com/product/1402/?pfm=rightcolumn_NewStuffFTW_4