Edit: Oh ya, and another thing (again.) The reason why you cannot get the 1MB filled up with coffee purchase after 6 years of trying and a lot of help from the media and regulators is this: Bitcoin SUCKS BALLS as an exchange currency. It is simply not competitive in this capacity and never will be. Sorry to be the bearer of bad news but you need to come to terms with this eventually.
For micropayments, then 0-confirmation works, but Bitcoin can't scale decentralized. Even if this is solved for BTC on a SC (such as my design does), there is still the remaining issue that private keys are a pain for users to manage. But this can be solved with hardware keys and M-of-N of them with multi-sig (since users lose things).
So I believe BTC can in theory (vaporware and all) be an exchange currency and decentralized. Do you disagree?