The companies cash in on the increased sales and the lower transaction fees they have to pay. {Double earnings} So they should show nice profit margins.
The should capitilize on this, and provide "discount" incentives for users, who switch to BTC payments, and in the long run re-coop those discounts, when they have large amounts of people, who pay with BTC
But they greedy ..."They want emmidiate gains" and this shows in their profits. {When the sales drop, they blame the BTC community, for not supporting them.
Overstock deserve what they getting now, because they pioneered merchant adoption. But they must pay back to receive more rewards. {Incentivised "discounts" for people who pay with BTC}
I agree with what you say overall, but... It's not just being greedy - you can't really have it both ways.
If they offer noticeable discounts to bitcoin users (more than just 2% that they save off CC sales) then they don't increase their bottom line. However, this is good for customers to want to buy and use
BTC as an alternative.
The other option is to note the savings gained by using
BTC and pass those gains on to the investors. This is good for increasing merchant adoption, creating good financial PR for Bitcoin and for keeping the investors happy (especially for a public company).
That being said, Byrne pledging a percentage of the savings to put towards Bitcoin adoption is a great step by this company. They (and Byrne in particular) are certainly doing more for Bitcoin awareness, PR and pushing adoption than any other big Bitcoin-accepting company.