1. To be fair, you and I don't see when others report spam, unless you are a moderator/admin.
2. Painful! In fact there are 4 new spam emails in Getting Started, but that would take me > 2 minutes to report, so I'm going to stop reporting spams, I just don't have the time.
I'm still pretty certain many of these are not bots but humans, or possibly just the sign up process is humans, which is why all the captchas and anti-bot registration plugins don't always work. Assume this is the case to be more successful in catching these.