I watched a video just earlier and I was not able to see it again since it was on twitter. I forgot to remember the name of someone who tweeted it because I was so amazed by what I was watching. Chinese people are using mobile payment. I don't know if it was a practice years ago, but that news struck me just awhile ago.
Do you like the idea of paying using your mobile phone? For example, you have 5BTC in your mobile wallet, can you track your daily expenses since the price is changing every minute. Do you think this will be a good idea to give your child his/her allowance? What if the price went down fast in a sec? Will you use it with a down price or will you choose to be hungry instead of making a transaction in a bad market price?
Are you prepared for this? Because the future has so much to offer. You should be more aware. We must be ready.
Well those Chinese apps use fiat money. Every government's wet dreams.
As for bitcoins it isn't exactly the best for transactions now because of the volatility as you've already mentioned. IMHO, many countries would probably go the Chinese path, with transactions in cash becoming less and less common but still using the fiat currency. Though this means some loss of privacy (the government can track your consumption) I think it might make it easier for bitcoins to coexist with fiat.
Just convert your btc and then send it to that fiat wallet and use that to buy stuff, no need to en cash anything. Basically just use BTC for storage.
Sweeden (and some others) have already managed to go cashless (OK, the public toilets are still working with coins in case of power outage, those coins are the remaining part of the cash in that country, but everything else is done by cards or mobile transactions).
So if they were able to do that, it's possible and I can imagine that goverment and the tax authorities are actively supporting this and would support this in every other country.
If you really want to have some privacy in a cashless country, you can try the prepaid debit cards, but you have to top it up somehow, somewhere, so it's not easy. But, if you have nothing to hide, you have nothing to fear... But privacy is a good thing to have...