From the forums:
'One down side to using EntityHome for generic crud is lack of built in security. One needs to be careful when using Homes for crud operations that allow or require RequestParameters. You need to ensure the operation on this ID is valid. You don't want to expose information you shouldn't and you definitely don't want to modify or destroy information you shouldn't.
For example, you don't want a user to update or delete another user's entity just by changing an ID in the URL and hitting return. Seam supports entity level security and you can probably extend a Home to double check access restrictions prior to operations. Likewise, you don't want private information available on lets say a user profile screen, to be available to anyone able to modify a URL.'