A personal appearance by someone (author, owner, etc.) is another way to lure customers and make the sale.  This requies that the person spend some time on site and meet and greet potential customers.

Some examples of this includes:

Author:  Get an author to appear on site to sign copies of his book which customers will purchase from your store.

Inventor:  Get the inventor of a product to appear on site to show how his invention works and sign autographs of purchased copies of his product.

Personal appearances can come at a cost.  There is normally a fee paid to the person to appear.