Why not? How are they worse than debit cards? If they are at least as good, or even just a bit worse, there are still a ton of benefits they provide that can help drive adoption.
There is no economy to back them, besides the one it is trying to compete with. The bottom line is goods will always be priced in bitcoins to be equal to their price in USD, so you aren't really revolutionizing anything except the name of how you are paying for the item. The goods and production of goods themselves will still be done with USD. You are simply convincing yourselves otherwise.
How so? Just the having to wait for only 2.5 minutes instead of 10 for a transaction? And why do you believe almost all hardware point-of-sale terminals and web shopping cart plugins are being developed for bitcoin instead of litecoin?
Bitcoin does not take 10 minutes for a transaction, no idea where you got that from. And I think all of those things you listed are being developed for Bitcoin because it came out first, and it takes some time for most people to figure out the bullshit that is really going on.
You cannot be both a cryptocurrency and a mainstream currency, it is an oxymoron. How does that not sink in to you people?