Amazon+Netflix+Internet = Libraries' Destruction?

Amazon is thinking about a subscription service ala netflix for books. OK, I've been predicting this for a while- but more as for a service for libraries to subscribe to. However, if this is offered like netflix, how much longer can we compete? Let's look at it, shall we. Netflix for $8/month. Internet for $15/month. Amazon for (i'm totally guessing here) $15/month. So, we've got $38 per month. Another couple of hundred per year for an e-reader and a roku box/appletv. That's about $650 per year. For a family of 4 that would be $162.50 annual per person. (the first year, this would go down to about $100/year/person after the initial device expenditures). San Francisco public library spends approximately $86 per capita. What happens when the cost in san fran is more than the companies? How long before libraries can't compete? When do we admit defeat? When is it going to be cheaper to simply provide the poor with their own devices and accounts?