Embargoes of Christendom were actually incredibly unusual in the medieval period. You have to remember that for, say, the Fatimids or the Mamlukes the taxation of trade going in and out of Alexandria was an enormous proportion of their revenue. The same would have been true around the Mediterranean.

So, per the Cambridge History of Egypt:

In the Mediterranean of the tenth to the twelfth centuries, men enjoyed an extraordinary degree of freedom of movement. The existence of political boundaries, even hostilities between governments, rarely interfered with the movement of persons or goods around the Mediterranean. Similarly, embargoes on exports or imports were very rare. The governments around the Mediterranean were much more likely to exercise their prerogative by claiming rights as first buyer than by banning merchandise.13

We can see the effects of this, for example, in the spread of the Black Plague, which reached Egypt via Constantinople.

So neither smuggling rings nor raids were necessary-- the period enjoyed basically unlimited trade as the taxation of this trade was the basis for state revenue.