Those independent id traders are a secondary life line of trade not only to corporations but a primary to unlawfull bases. Don't get Indi ID traders mixed in with Corporate shippers or you will kill your own deliveries to your very base. No, smugglers won't be able to compensate for the demand since they can no longer land at any lawfull installation who captains a pirate train, which now puts indi ID traders as a priority for supplies to unlawfull bases since no corporate shipper can deliver to unlawfull bases, you need indi ID traders and such.
Corporations depend on Indi ID traders to get things to other customers which may not want to be associated to, lets say a food manufacturer whos primary customer is say..... CRETE. Since having such a customer would taint any political or public relations, one company would contract a indi ID trader to make such deliveries, and Crete (Corsairs) would be thankfull for it.
or
Unlawful group need supplies but corporations wont sell to them, unlawful group would hire an Indi ID transport to go pick up supplies on there behalf at a legal base, and return to drop off.
In additions, corporations need these Independent traders to go to say conflicted areas, which they do not need to risk their own resources and transports, this negates company risk and lays it more in the hands fo the trader. This is good business for corporations in turn and risk factor dropped considerably
Indepentent Traders are needed! Don't bite the hand that feeds you.
Mercs I thinks should be limited to no tradings and Freelancers limited to frieghters, but you Intependent Trader ID are the secondary life line to the economy and be allowed to continue.