Of course, in reality, the chance of an increase in value pretty much balances out the risk of a decrease in value. If you want essentially zero risk, Tony provides that service, and it's still cheaper than credit cards.
Yes, but HOW... I would either need to shift my whole cart to a new platform, or do everything by hand (and still pay the exchange fees). Both increase costs. taking bit-pay as an example I only save .59% over pay-pal (16 cents on the average transaction.)
Perhaps, but you do save. If the bitcoin trade volume never amount to much, you've lost nothing for trying it; however, if the trade volume justifies a lower cost method, you'll be motivated to make it happen at that point even if no one already has.
Still, I'd wager that, now that the developers know that there needs to be a plug-in for 3Dcart, it won't be long before you have what you need.