If everyone researched their purchases, there would be no society. People would spend 24 hours researching and trying to decide what to eat for breakfast, nobody would sleep because they'd have to spend 20 minutes trying each of the 10,000 matresses available at every furniture store in the county. Audio, TVs, cars, boats, house paint, toothpaste, clothes, sneakers, pets, childrens college, et cetera et cetera et cetera...... Everybody just needs to make impulse buys, otherwise nothing gets done.
But I stress: The more it costs, the more you should research (I'm looking at you Mr. Snooty-Gourmet who reads 5 magazines a month and gets on 4-month waiting lists to eat at the latest pan-europa/thailand club, who shows-up in his $60,000 sedan that he's never driven over 35. Its frickin dinner, just chill-out).