Combs serve a purpose.  Hair stylists use them, as they create a single straight line for scissors to use as a trimming guide.  They fit snugly into a pocket or purse, plus most have two combdrumb (thanks, wikipedia!) options, depending on whether you want your hair flowing via mini or wide.  They're easy, cheap promotional giveaways as marketers can print their business info along the spine.  In junior high, I tried a hairbrush.  More expensive, sure, plus I have 641 options of brushes at the store to choose from - natural vs. synthetic bristle, flat brushes, shape, those with teeth which go all the way around the stem, softness/hardness, whether they should have plastic balls on the ends of individual bristles... It's crazy and way too much effort to select one.  So I use my wife's.  Thus far, the only complication is when her long locks collect on the brush and I have to somehow reach between the bristles and clear the snags.  Which, coincidentally, is the only purpose a comb serves for me anymore.