I think you're conflating two very independent aspects of the Bitcoin story - the protocol and the exchanges.

The protocol itself is responsible for transferring bitcoins from one owner to another. It doesn't need external accountability because it's defined mathematically. It's either secure, or it's not - that can be proven through analysis of the protocol, independent of any government agency.

That, in itself, is really uninteresting to the public at large. The real question is how the coins should be valued.

That is dependent on a ton of other factors, most notably how bitcoins are used and how they're exchanged for fiat currency. You're pointing out two major issues - the lack of products and services that can be bought with bitcoins (which causes the value to be highly volatile and dominated by speculation) and a lack of trusted exchange agencies (like banks) to provide accountability.

If you put in usd5 and get nothing, you absolutely have someone to sue - the company you used during the exchange (for example, the owner of this ATM, or sites like mtgox.com or btcchina.com). But that has nothing to do with the protocol described earlier. For the same reason, the protocol does not track any value. It's responsible for securely transferring bitcoins, period. There are however many exchanges where bitcoin's value in different world currencies is tracked (good resource here: http://bitcoincharts.com/markets/)