there is spider software that goes thru and pulls them all out. also spammers will literally try a bazillion combinations on a domain. like
[email protected] then
[email protected] etc etc just throw a million combos and hope to hit a few
you can also View Source off the browser view menu then search by "mailto", thats the html command for an email address. the email address will be right behind the words mailto like this:
<a href="mailto:
[email protected]">Email me</a>