Okay so we covered how "there's only ever going to be 21 million of them!" is a non-issue, now I see we have moved on to "but people find it hard to deal with more than two decimal places!"
Can we agree that if Bitcoin is ever to be wildly successful, we are still a very very long way, if ever, from Bitcoin being the primary currency of any society? And in fact that may never happen and isn't even something that
needs to happen for Bitcoin to be considered a success by some people's metrics?
If we are working from that assumption then it also follows that in stores and on web sites, goods and services are going to continue to be denominated in the primary currency of the region. So let's say $ for the purposes of discussion.
In which case it is going to be down to the Bitcoin user's software to perform a meaningful conversion between $ price and
BTC price. And many of them already do this in exactly the following way.
So, for example, something today on sale in a store in the US for $123.45 might be purchased for
BTC0.27310739. Instead of the Bitcoin app just showing:
BTC0.27310739
it would make sense for it to instead say something like:
mBTC273.10739
(About $123.45)
Also in a world with much greater adoption of Bitcoin we would assume that the fiat to bitcoin exchange rate will not be so volatile so people will be used to knowing that "one $ is worth about m
BTC300" and not see that swing massively on a daily basis.
The use of m
BTC here is just an example and in reality it will settle down to whatever denomination makes the most sense.
That's already how Android Wallet presents sums, and I find that pretty intuitive.
So again, I do not see the presence of more than two decimal places to be a major issue.