I used :3 back in the early 2010s a lot. These days we just have so many fancy emojis. I guess it has just fallen out of style in favour of more flavour full modes of communication. Or really cringe shit like this
I didn't know the c was a paw until I saw this post. I guess I thought it was just a typo after the kitty face that somehow caught on, like people putting 1s after exclamation points.