> the world is full of people who feel very different paying $100.00 vs $99.99

Agree, though that effect is not constrained to Bitcoin. Retail orders, for instance, follow Benford's law. This is despite well-documented psychological biases towards e.g. certain digits, whole numbers, round numbers, et cetera [1]. Benford's law [2] derives from deeper mechanics.

As you point out, however, a better control would have been not all prices in public stocks, but retail orders.

[1] https://mro.massey.ac.nz/bitstream/handle/10179/2695/02_whol...

[2] https://en.wikipedia.org/wiki/Benford's_law#Krieger–Kafri_en...