Interestingly, this was probably due chiefly to observer bias. Serious Eats tested whether or not "better" eggs tasted better[1], and came to two conclusions: any perceived improvement in flavor is due exclusively to a darker yolk color and to the
belief that the eggs come from a high-quality source.
They did a similar test with mexicoke[2] which produced a similar conclusion. People prefer coke in glass bottles, and they prefer coke that they believe was made with real sugar. When both of those variables are controlled for, they actually prefer HFCS coke.
That said, we never actually eat our food double-blind so even if any perceived difference in flavor is due only to observer bias, it's still important! After all, the whole point is to please the "observer".
This also isn't to discount the difference between low and high quality versions of other foods. Grocery store tomatoes (beefsteak mostly), for example, were bred almost exclusively for shelf life and transportability, with flavor suffering as a result.
[1] http://m.seriouseats.com/2010/08/what-are-the-best-eggs-cage...
[2] http://m.drinks.seriouseats.com/2011/09/the-food-lab-drinks-...