In an effort to combat the functional equivalent of human trafficking, Egypt has a law that prohibits men from marrying women more than 25 years their junior. While one might argue that a 25-year-old woman marrying a 50-year-old-man could pose some problems (but often doesn't), it doesn't seem to me that it ought to be outright illegal, but that's not really the point of the law. The problem in Egypt is that some of their wealthier Gulf neighbors have a habit of coming to Egypt to marry extremely young women, as was the recent case in which a 17-year-old found herself married to a 92-year-old man, presumably for a hefty dowry of some sort.
The Ministry of Justice has refused to endorse the marriage, which will make it impossible for the man to leave the country with his bride. However, there is of course a loophole. If the husband deposits money into an account at the Egyptian National Bank in his wife's name, the Ministry can approve the marriage. Last year, 173 men deposited an average of $80,000 USD and subjected themselves to some unspecific screening in order to marry their much-younger wives.
I mean, Egypt sounded kind of cool there for a second, right? Like all, "we don't countenance child brides or women being sold of like such chattel," which sounded great right until I got to the part where it's cool as long as you pay the government in addition to the family. Sigh.