Should you farm out your open houses? Agree or Disagree!

I've read that only 2% of all homes are sold through Open Houses. That's not a lot, to be sure. Since agents routinely hold houses open one has to assume that the main reason they're doing so is to try and pick up new buyers. But how does that serve the seller? They're being inconvenienced so you can pick up new business? What sellers care about is selling their home. To assure my seller's interests are best served, I never have other agents host my open houses. I've seen too many instances of bored agents at open houses (e.g. not even getting up when you walk in the door) or agents who are not knowledgeable about the property (since it is not their listing). What do you think? Practical or impractical, don't you think sellers are better served by the listing agent holding the house open rather than farming open houses out to agents who are hungry for new buyers?