If an attacker compromises the page or does a man in the middle and injects a form that isn’t displayed, it can trick your password manager to auto fill your login information and then send it anywhere. But that’s just one vector and if an attacker has compromised the server, there are a number of attack vectors they could take.
In some cases they literally prescribe methamphetamine. It’s sold under the brand desoxyn. My ex girlfriend had it. Since then, I’ve stopped conflating the two. They are similar but not quite the same.