Add products only in subcategory or also in the main category?

Hi,
I was just thinking about something.
Is it better to add products only in the subcategories where they belong or also in the main category.

For example:

I have “ Red Apples “as a product.
The main category is “ Apples” the subcategory is “ Colored Apples” .

Should I only add the products in the subcategory “ Colored Apples” or also in the main category “ Apples” .
If I only use the sub category ,the main category will be empty and will only have the sub categories.

Or if I put the product also in the main category the main category will be a mix of all subcategories.
And what about seo?Cause if I add the product in the main category and sub category I have this product twice.

This was just something which come in my mind.

How do you handle this?

Just a bit curious about your experience.

Richard

Zen Cart is structured to hold only either products or subcategories in a category. You cannot add products to a category which has subcats, and vice versa.

If you use sub-categories then all products must be loaded into their relevant sub-category. If you put products into the main category as well then your customers will only see those products.

Vger