Given that Samsung has stated online and in product literature (instructions that come with accessory docks) that a Froyo update is forthcoming, I don't see how they can charge any carrier for it. Considering that a feature of the docks will not work without Froyo, they are either fraudulently selling these accessories or already committed to providing the update at their own expense. Either way, they are in violation of FTC rules and should be brought to explain why we are still
waiting for this promised update.
Oh, and why is Google inactive on this? It hurts the Android platform as much as it hurts Samsung and AT$T for this kind of shenanigans to be going on. While I'm no fan of M$, they wouldn;t stand for any vendor screwing around with Windows like this.