People that are inclined to take the unnatural step of forsaking basic physical needs are attempting to deny them for a higher purpose. Why would they want to deny them? They are told that homosexuality, or just sexuality is wrong. Not all of those that seek to serve, but enough for it to be attractive for a future priest or nun to "save" themselves in this way. When they fail, they fail big. Needs denied have a way of bursting through in a very large way.
IMO, the church needs to get rid of the celibacy as a requirement to be a priest, and erase the stigma of sex as a sin. The Bible clearly teaches that sex within marriage is God inspired and blessed, allow these people to have a full life. It will make them better "servants of God".