so nice to see a successful businessperson who is not all about fucking people over. i'm guessing he's offering 3% because that's how much he saves without having to use the normal mediums (like visa).
He saves only 1% using Bitcoin. Visa / Master charges a discounted fee of 2% on Overstock, while Bitpay charges 0.99%. So it is just 1.01% and not 3%.
Considering that monthly Bitcoin sales in Overstock stands at some $250,000, every month Overstock might be spending some $7,500 for spreading the message of Bitcoin (give-aways, promotions?).