This sounds apocryphal. I don't doubt Yeltsin was impressed by his visit to the supermarket, but by 1989 the writing was more than on the wall for the demise of the USSR. I imagine it'd be more accurate to say that Yeltsin was excited by the prospects of a transformed economy, seeing the prosperity of the U.S. firsthand, rather than his visit being any kind of tipping point in the Soviet Union's downfall. Anyway, Rob…
(This is why when I travel, I go not to the center, but to the fringes of the cities, to see how the common people live.)
And I'm sure this contributed to his ideas of how the country should be like.