eh you lost me, man. he still has the option to only take USD or use a 3rd party payment processor. At the moment, it seems that this approach is not costing any businesses in sales, since Bitcoin is still used infrequently as currency. The only point it actually becomes a currency itself is when the shop owner stops using a 3rd party processor and says "you know what? I'm comfortable just holding onto these". With the market volatility of Bitcoin this is unlikely to happen for a while, unless they are among the believers who think the value can increase indefinitely and accurately represented by trading prices.

I definitely understand the value as an infrastructure, but this is the web. Better solutions will emerge and could just co-opt the Bitcoin infrastructure. Like the way ISPs came in and bought access to the data lines of phone companies, same idea.