Taxes is an obligation for every citizen of a country which obligating their citizen to pay taxes. However, if you avoid paying taxes then you might be punished so it's always better to be a good man and always pay those taxes. If you are still having intention on avoiding taxes then it's you the one who will be responsible for everything you have done
But so far I haven't seen country which taxing directly onto bitcoin but only taxing you when exchanging your bitcoin to your local currency so, lucky you.
To pay taxes is really a duty of every citizen, but you forget that this is a road with two directions. There is still a duty of the state to fairly distribute the taxes and to deal with the embezzlement. People see that the state does not fulfill its obligations and therefore do not want to pay taxes. What's wrong with that? I did not pay them. I take nothing from the state and do not feel obliged to him.
Since earning bitcoin is not included as regular income of one citizen, I guess it's great because it was not included as taxable income of each person. Otherwise bitcoin is not regulates by the government of some country that's why they cannot obligated to pay taxes.
However if the bitcoin started to adopt by the government of each nation I think crypto currency are need to follow the rules and regulations of respective country.
Moreover earning income of people from digital world will be lessen due to tax deduction from their income.