Has anybody gotten an account banned based on IP alone?

For example, say you were on an IP doing some black hat stuff and your infringing account got banned along with other accounts that shared the IP but weren't doing anything black hat.

Or another example might be you were on a shared proxy and not doing anything when FB decided to block the IP due to abuse and your accounts that happened to be using the IP got banned.

I honestly don't think these types of things are happening but I'd like to know if I am wrong.