We have all heard the story of the pizza guy getting paid in BTC, yet some 10 years after Bitcoin was made, hardly any shops accept BTC in the great scheme of things.
There are few reasons why alot of shops don't accept of bitcoin payment method, it could be due to high volatility of the market, or maybe due to the high cost of transactions or time taken for the other party to receive the bitcoin, but one of the main reason would be due to regulation policies, since the government is against the use of bitcoin in several countries, some even threaten to jail anyone who makes use of it,so there's absolutely no way shops in that country will accept bitcoin payment as it is prohibited in the country.
It started off as a project that would enable the regular guy with a modest pc to mine BTC, now you need a huge farm to be able to mine effectively.
Hard to mine is also what adds value to bitcoin, cause not everyone can mine it unlike back then when it was quite easy were the early to find blocks,there were less users of bitcoin back then compared to now, so you can't expect it to still be that way.