The question is asked – and Arnon's answer is given – based on the assumption that biases play a role only in "momentous" descisions, that is decisions that are relatively rare and can profit from rational consideration.
But biases play a constant role in navigating your everyday life. For example, you don't do the Pepsi Challenge every time you buy food. You just pick the joghurt that you know you like (bias), or whose list of contents appear most healthy to you (bias), or the price of which you find signals quality (bias) or is cheap (bias). Assuming that you understand the effects of food packaging, placement, shop lighting, muzak, shop aisle geography, price structure, advertisement you don't even remember having seen, etc., and can ignore its effects is just another bias. And maybe you are a nutritional scientist and actually (think that your science enables you to = bias) know what is healthy food, you probably are not a psychologist, financial expert, political scientist, sociologist, and so on, too, and will have to rely on hearsay (bias) or experience (bias) for most of your other decisions. And since you are almost constantly making decisions throughout the day – which turn do I take?, should I brake when the traffic light is yellow?, is it worthwhile to fight this out with my wife or will we have better sex when I let her be right?, should I correct my son or am I being overprotective?, what clothes should I wear today?, will it be fun to watch tv or will I have more fun tomorrow if I go to bed now?, is this online debate really worth my comment?, etc. etc. etc. –, and rational decision making is effortful (Baumeister), most of your decisions must be made heuristically.
Removing biases and forcing you to rationally process all information would leave you overwhelmed and unable to function. You simply don't have the time and mental resources to make every minor decision rationally. Biases are absolutely necessary for your survival. Without them you are reduced to a state similar to that of a toddler, who has yet to acquire biases, i.e. develop this mechanism that automatically filters the relevant from the irrelevant.
Of course biases can lead to wrong decisions. But these errors do not indicate that you should abandon all biases completely, but that you need to refine those that are misleading to more accurately reflect reality.