I use Excluding / Including fields for fetches a collection and binding its to a grid but the result grid will remain the fields headers? (the grid show header of the fields removed with empty colunm content).

Normal. The values of the fields were excluded from the fetch, but the fields are there in the entities.

You'll need to edit the Grid's Columns list to hide or remove the unwanted fields.

Thks and I have one question, please help

what is the diff between these line of code

CustomerCollection customers = new CustomerCollection();

and

EntityCollection<CustomerEntity> customers = new EntityCollection<CustomerEntity>();

The former is a Typed Entity Collection, these classes are generated when using the Self Servicing Template Set (only).

The later is the Generic form, please google for .NET Generics for more details.