A homepage or fan page is like an index.html - it should be the first page you arrive at. It would have either a username or a single number group after the facebook.com/
Fanslave credits you for visiting these pages:-
IF they exist
IF the name is spelled correctly
IF the user has abided by facebook's many rules, such as numbers of likes, etc.
Cheaters take you to another page - seen by having a doublenumber group in the url, normally with a ? between them. For whatever reason, the app or fanslave doesn't credit you for liking these pages.
In fact, you'll notice that many of these pages don't even have a 'like' button.
Now, any reasonable webpage creator can quite easily obtain a script, available in many languages, that would look for that '?' and block the page.
So why doesn't fanslave?