The same reason husbands look at other women...because they can and it's ok to look as long as you don't touch!!!
The real question is why do husbands look at other women....Wives look at men because its our God given right lol.....Perhaps we are searching for a cute butt, which the husband doesnt have or maybe even someone to fantasize about while making love to her husband.,,J/K..As everyone wants to say Its okay for a man who is in a relationship to check out other women, I suppose its the same thing....No one will never have an answer to this one...Whether male or female we all do it because we can....don't worry...
Some wives are so honest that they don't even do that..But on my opinion, why is it wrong for wives to do that and it's alright for husbands to look at other women..So to tell you the truth I agree with "Bld6957" that it's ok to look as long as you don't touch, especially you better not compare someone else to you're wife..