If that wasn't the case, then people also would never sell their Bitcoin.

People sell appreciated assets so that they can buy other appreciated assets or spend their winnings. But that's cashing out, not the kind of day-to-day spending that money is for.

Anyone who can't afford to save will spend, and if BTC is what they get paid in, then BTC is what they'll spend. But money trickles up, and every BTC that ends up in a rich person's hand will stay there too long, decreasing the money supply, causing deflation, and otherwise screwing up any economy that is trying to run on the crap.

That you think of profit-taking as "spending" gives away your very deep ignorance of what money is all about. Money is the stuff you don't hold for appreciation. Money is what you spend to buy assets to hold for appreciation. Assets like Bitcoin. Yikes.