This. Search for a product in google shopping and multiple merchants will be clustered around one product image that is chosen from 1 of the merchants. That's t

This. Search for a product in google shopping and multiple merchants will be clustered around one product image that is chosen from 1 of the merchants. That's the main reason, but it also avoids the ugliness of an ebay search where seemingly every other merchant has bright/bold text claiming free gifts or other such offers.