(More details on Droit de suite at Patry's blog).
If a system similar to Droit de suite was in place for ancient coins perhaps some source countries might come to believe that a trade in ancient coins is good for national pride?
I suspect that many of the restrictions on the coin trade were the result of source countries feeling left out of the market, and not a result of a strong national feeling about coins as cultural property. Here is a quote from Burton Berry's Numismatic Biography:
By the late 1950s, a new a strong trend was developing the
concerned every collector of ancient coins living in the Near East. First, prices were rising rapidly. Coins that I had purchased on the 1930s for $50 each were selling in public auctions in Switzerland for $1000.... And, more important, the attitude in the Near Eastern countries toward collectors was changing. Where formerly everybody was eager to help the foreign collector, people now were becoming suspecious, and even envious, that you, the foreign collector, saw value in objects in which they saw no value. Newspapers began to give prominence to stories of inflated prices that some antique objects brought abroad, and it was then but a step to accuse foreigners of carrying off the wealth of a nation! Certainly, there is a genuine grievance where newly discovered works of art are exported without authorization or where farmers are encouraged to dig for treasure on archeological sites on their land.... Many old friends who were officials had retired, and their replacements, regardless of their private feelings, were to this
new trend and found it expedient to go along with it.
Coins have never had a 'resale right' or tax sent directly to the creator, so at first it may seem rediculous to send money to the current government of Egypt whenever a Roman Egyptian coin is sold. Yet paintings didn't start out with a Droit de suite right either but the law is strangely popular and now covers California! Perhaps a new tax on antiquities, which could be called a 'right', would be beneficial to both collectors and source countries?