why do Contributors have access to edit my main page?

This issue only occurs with publishing templates. With collaboration templates, Contributors do not have any Site Actions menu choices.

Some people go off making permission levels to fix this. This will not work since Contributors still need Edit & Delete rights to the lists in the site.

This issue occurs because in sites created with the publishing template, Contributors have Add/Edit/Delete rights to the Pages document library (which is where the home page is typically stored).

The simple fix for this is:

• break the permission inheritance for the Pages doclib
  
• change the permissions for the Contributors (probably Home Members) to only allow read access
  

Although the Site Actions menu will still be present, Create Page and Edit Page will no longer show up!

Regards..