Hey, I really like the 2. and 3. point you made about "They are global" and "ALmost untraceable transactions". I want to add to the 1. point about inflation that inflation is not necessary a bad thing - the economic theory agrees that deflation is much more harmful than inflation and hyperinflation is, of course, the most harmful (look at Weirmar Republic in 1930s). The reason why central banks are trying to keep it around 3% is that there is a 3% buffer against deflation and at the same time 3% is not that large to have all the negative effects that are associated with hyperinflation.

Also, inflation does not happen just because the central banks are printing money (these days, not even this is happening. They do it by buying and selling bonds on the market). A more prominent cause of inflation happens when the unemployment is low => there is not that much high quality labour on the market => firms have incentives to raise salaries to keep their employees => this will cause the products that the firms are making be more expensive => that is inflation.

Of course there are other reasons but this is the gist of it and moreover, all of the reasons are still "kind of" a theory. After all, economics is a human science so nothing is certain.