To some extent I think it's a matter of how much time people have available. I probably wouldn't have the time to find the distiller at an auction or sale for $2, but I certainly could find it online for $90 and would take that route if I was buying one. Brand names also carry a lot of weight for people, and they'll pay the extra money for that sense of security (even if it's unfounded).
I also think that based on income people have different thresholds for researching a purchase - i.e. if someone is making a lot of money they don't sweat dropping an extra $100, while most people will. My threshold for researching a purchase is about $50-75, but I can certainly understand that others have different thresholds. While I certainly know that with some effort I can find some things I buy for
much less at garage sales, on Craigslist and such. It takes time to do that, and I'd rather spend my limited free time hanging out with my daughter instead of spending hours driving around searching for the best deal.