The progressive / regressive terminology takes it for granted that income is the right denominator to measure against, rather than consumption, which is not obvious in my opinion.
In my experience, it's generally been the case that rich people are anti-consumption, at least on a personal level. Poor people often splurge on luxuries to relieve some of the pressure of grinding poverty. They buy things to signal status in order to attract a partner. A sales tax on luxuries like this is effectively a wealth transfer from the poor to the rich, not altogether dissimilar to government-run lotteries which fund scholarships.