wp_post table database question

I post this question in this forum and that of the plugin in question just in case the plugin developers attempt to remove my post to protect any issues with their choice of database integration…which I note is not the same with a few other ecommerce packages in wordpress.

Now to my Question

Would the following be true about WP Ecommerce and any other ecommerce package that inserts its products into the wp_post table rather than a specific products table..?

I notice that WP ecommerce stores products in the wp_posts table. Im a little confused by this…how do the entity relationships between categories>subcategories and products>sub products work in “1 to many” and/or “many to many” relationships if they are all stored in the same table???

If that is true, once the wp_posts table begins to fill up with product and post data… the database is going to progressively begin to run awfully slowly (based on the number of records/products stored in the table…and use considerable system resources in trying to wade through hundreds if not thousands of repetitious records in trying to select the one to be.

one would believe that it would be almost no better than accessing an entire txt document of records for the appropriate record to be displayed!!!

how does WPress resolve this problem???

Is this why some say on forums that WP e-commerce should not be used when more than 5,000 products are in the store database???

kind regards
adam