(Mike Mozart)When you buy a jug of mayonnaise or a mammoth pack of toilet paper rolls at Costco, you understand that you’re saving by buying in bulk. But then there are the $4.99 rotisserie chickens that you don’t have to buy by the dozen to get that low price. In fact, Costco is the one getting the short end of that deal, missing out on millions a year by keeping the price low. Speaking this week to analysts about the wholesale club’s quarterly earnings, Costco chief financial officer Richard Galanti answered a question about the company’s philosophy on the cheap chickens. “I can only tell you what history has shown us: When others were raising their chicken prices from $4.99 to $5.99, we were willing to eat, if you will, $30 to $40 million a year in gross margin by keeping it at $4.99,” he explained, according to the Seattle Times.