Data is encrypted when you access a HTTPS site, but not with HTTP. This means a third party can view your connection to the site, and any information submitted by you.

The connection to HTTP can be exploited, and malicious script can be injected to the response you (the user) receive from the server. This can include ads that drain computer resources (memory, CPU usage), or attempts to exploit vulnerabilities within your operating system/browser. As there is no authentication used with HTTP, there is no way for the user to know if the request/response has been changed.

It is considered generally safe to just browse these sites without inputting sensitive data, but the above is something to be aware of.

Would breaking a ton of rules and getting the account banned remove all the content?