Most people prefer using bitcoin as a medium of exchange.
Did you use Bitcoin to pay household bills, taxes, and regular shopping? I doubt it, you'll still use fiat.
Bitcoin is not really good option to pay regular shopping due to high volatility. You'll need to pay higher fees for get confirmed faster, or you'll need to wait until the price is same as your purchase.
Yep, I agree, at least for now. Bitcoin's volatility alone could be a big hindrance when paying for shopping or service. To someone who is doing it right now, I can say, they are really supporting the progress of this technology, but I won't blame those who don't at the same time, as most people in crypto space are seeking to make good profit.
Tx fees and speed won't be a problem in the near future when LN transactions are flawless.