I could add each IP to the ban list, but I'm always a little concerned I might end
up shutting out someone legit.
To expand on what you've brought up...
This could also block out many people with shared IPs or Proxy servers. Think; Internet cafés, schools, hotel chains, corporate buildings, ... AOL subscribers (is that still a thing?)...etc
And what happens when the coworker/sibling/partner of a positive contributor to your site, decides that it would be funny to create another account and spam your site with gibberish and troll-bait... "just because."
If you block an address/range of addresses, you're blocking everyone from that IP, not just the "jokester."
