Credit also goes to Wecx, Coretrolls.info, John M (Beta Dollar), CryptoWyvern for ideas.

However, zero-conf is much more of a problem in regards to miner attacks, and edge exploitation cases. The chances of it happening with a small ticket item from a merchant is extremely extremely low, and also not profitable for the double spender. The effort that goes into double spending for the average consumer purchase just isn't worth it. Thus, zero-conf is pretty safe for merchants. Counterfeit cash (which is essentially zero-conf unless they check every bill) or credit card fraud is also a high risk for merchants, the chances of zero-conf being a problem for a merchant is very low in comparison. As long as the item is not big ticket like a computer or car, then zero-conf is almost completely safe, and the loss would be tiny if such a attack went through. So zero-conf is one of the most awesome original features of Bitcoin, until it got removed by Bitcoin legacy. So what is the problem? Even if we fixed the non-existent double spending on zero-conf,

it still looks untrustworthy to a merchant currently unless they know a lot about Bitcoin.

(It's a presentation problem) This is just being in the shoes of the merchant. Zero-conf sounds like NOTHING has been verified. I know it's cheating a little bit, but

I think naming 0-confirmation to simply "verified" will go a long way to changing this perception.

To me as a merchant, if you say "verified" but 0/3 confirmations that's good enough for me.

I get that it's not 100%, but it's good enough