You're assuming that because the device is subsidized, that this is somehow a value for the consumer. Cellular service companies don't subsidize phones because its good for the consumer, they do it to lock users into a service they might otherwise move away from for better terms and conditions. This is more valuable to the service then the consumer.
This is a calculated move on Amazon's part to build a lucrative ad network. This isn't evil per se, but it's certainly not in my best interest as a consumer. Personally, I've done a fair bit to cut down the number of ads I see in a day -- I dropped my cable TV because the number and frequency of ads lowered my enjoyment of the programming. I've stopped buying gas at stations that blare ads from their gas pumps. So, I certainly wouldn't buy a device that wants to charge me extra to not see ads. Out time and attention is more valuable then the shells and trinkets being offered by these companies.
Most consumers prefer to get a free/lower cost phone in exchange for a contract commitment. Whether the "value" to the consumer stands up to scrutiny in financial terms is not really important; most consumers like it, thus it is a value to them.
This is a calculated move on Amazon's part to build a lucrative ad network. This isn't evil per se, but it's certainly not in my best interest as a consumer. Personally, I've done a fair bit to cut down the number of ads I see in a day -- I dropped my cable TV because the number and frequency of ads lowered my enjoyment of the programming. I've stopped buying gas at stations that blare ads from their gas pumps. So, I certainly wouldn't buy a device that wants to charge me extra to not see ads. Out time and attention is more valuable then the shells and trinkets being offered by these companies.