I've never understood why those against increasing the blocksize *insist* that their opponents are always about "paying for cups of coffee".
Honestly it has been exactly "cups of coffee" that many of the large block size proponents have been using as their own mantra (this particular use case certainly didn't start with me).
In any case I am referring to small payments that currently you would be far more likely to be using a credit card and for which reversibility is something that one would want without much hassle (you don't want to have to involve a lawyer to get back 10 dollars from a bad merchant).
Again for person to person transactions Bitcoin works extremely well (I have purchased Bitcoins for RMB in the past for people that had visited China a few years back).
most things like cups of coffee in starbucks wont need confirms or reversibility.. because the coffee buyer can slap the barrista in the face with a wet fish if the customer doesnt get their coffee after payment.
but if your talking about a $4 keyboard and mouse from some chinese supplier.. then thats slightly different.
that being said the news has reported that silk road alone has done millions of small transactions even with nefarious merchants and there hasnt really been a problem with the buyer-seller relationship.
so buying a snickers in a walmart or a coffee in starbucks is no issue at all. they have their own codes of conducts which protect customers no matter the currency. the only issue is the 'stranger danger' transactions with people thousands of mile away.