Why? Why should there be a percentage-based fee at all for financial transactions? This is an idea that credit card companies have pushed onto the world, but there's no reason it needs to be accepted as fact.
I didn't really mean all. I did say between strangers and especially when the two are not face-to-face. Two other qualifiers: 1) when "good funds" need to be transferred immediately and 2) for dollar ranges from around $10 to $1,000. This makes up the vast majority of retail commerce for which credit cards are so well suited and widely used.
Best approach is to look for areas where credit cards are not widely used instead of trying to displace them in areas where they work really (really, really) well.