They obviously don't care about lots of types of traffic.
If you watch some technology related keyword with search, anytime some stories from that keyword hit the tech blogs, you get a spam storm of hundreds or thousands of identical, useless tweets linking the post. I guess I'm being presumptuous, but that looks like they aren't doing anything at all to limit activity like that.
Twitter is a publicly traded company and one of their metrics is tweets per day. Spam is in their best interest. Same goes for snapchat. It's a bit twisted but when snapchat or Twitter can say "X million photos/messages per day," who cares if it's all spam? Who's gonna prove them wrong?
If you watch some technology related keyword with search, anytime some stories from that keyword hit the tech blogs, you get a spam storm of hundreds or thousands of identical, useless tweets linking the post. I guess I'm being presumptuous, but that looks like they aren't doing anything at all to limit activity like that.