Cutting off a peace of foreskin is like cutting off someone's eyelid. You might say "its just a peace of skin", but it also contains almost all of the sensitive nerves in the penis. It is also primarily done for religious reasons. Also, a child cannot consent to circumsision, so yeah,
Male circumcision does not (in "successful" procedures) inhibit the male from enjoying his member. FGM takes away any and ALL capability of the female to enjoy herself and needs. Also, the practice is done with poor tools which lead to deadly infections that not only infect the immediate site of the procedure, but can also damage her internal reproductive organs from the inflamed tissue. All for the sake of a woman not having those "urges". There are no benefits to this procedure for a woman whereas it could be argued that a foreskin removal can allow for full erections if the foreskin was to tight.
Females subjected to genital mutilation are usually forced to do so primarily due to religious beliefs. Males that go through circumcision either get it done at birth or choose to get it later in life (I believe it was historically a practice done under Jewish faith), but the difference is that male circumcision doesn't nearly have as much complications as female genital mutilation does.