Ads are not the only model for providing free rides. Other Sustainable models exist:
Peer balancining: producers earn free credits for consumption. This is how Internet backbone peering and Team Fortress 2 work.
Freemium, or light users are too cheap to meter, while heavy users pay. This powered Zynga's IPO and many prosumer niches like Photography and web analytics.
Open core with professional services for customization or support (a mix of Freemium and free software). Cloudera.
How is Facebook different from telephone service, or USPS, or an ISP, under your analysis?
(Sidenote: USPS actually is ad-supported by bulk mail, and "heavy users subsidized" by parcel post. First class letter postage is really a nominal fee to eliminate DOS and DDOS attacks. )
At the that scale, CPU and developer time are mostly orthogonal. If you need to crunch 1000x more numbers, you won't be able to program your way out of the problem. If your code is 1000x inefficient, it should be easy to optimize a bit. If you really need 1000 machines for just one hour, setup costs dwarf compute costs. If you need 1000 machines for a year, you will need someone to administer the work and wrangle the data.
Amazon fails over data centers at least once a year in fire drill testing. Amazon has more backups, testing, and monitoring than 99.9% of small or midsized organizations.
To precise, pharmaceutical companies are concerned that bad counterfeits will harm the reputation of their products, which will cut into order volume and profits.
Why would you use a credit card company that locks yo right account, ever? Fraud is the merchant's problem, not yours. Fraud investigation is a courtesy you provide to merchant customers, so the CC company should never have any reason or lock your account without your permission, unless they have tried and failed to reach you for close to the fraud-liability time limit.
It takes less energy to accelerate an object away from both the Earth and sun (assuming your launch pad is on an appropriate spot on the Earth surface), than to accelerate an object away from the Earth but into the sun without just getting the object stuck in an orbit like Venus or Mercury.
is even faster, but also missed the point.