Well, they werent smuggling weapons INTO Egypt.
Egypt has laws about that…
They were letting them smuggle weapons into Gaza. In exchange for Hamas and the Muslim Brotherhood(two peas in a pod) to not do any naughty things in Egypt.
Basically the Egyptian government was letting the Muslim Brotherhood arm Hamas as long as they did not do bad things in Egypt.
Sounds similar to what the FBI did with the Fast and Furious selling weapons that were only supposed to be used in Ol Mexico.