I doubt losing my business will cause anyone willing to price gouge to change their practices, but who knows what other evil things that kind of company will do to exploit you so I'll feel even better supporting a business that didn't go out of their way to take advantage of people who are struggling.
I suspect that Markups will remain relevant for as long as the situation vis-à-vis car dealerships and how they operate persists in the US. Markups may even prove to be instrumental in successfully rallying and focusing consumer support sufficiently to overcome the status quo, and so eventually have no further reason to exist. But the word "eventually" in the previous sentence is key.
[1] https://www.opensecrets.org/industries/lobbying.php?ind=T230...