No. they are not actually required unless you are a hardcore road-rider (for them it is a must have feature). Long distance endure and cross country riders may sometime prefer clipless pedals but for downhill riding, a practical rider would prefer fat tire with standard flat pedals and a pair of comfortable sneakers, because they often need to put their feet on ground. On unknown trails, a long distance rider will also prefer platform pedals due to their flexibility and versatility.