The Ottawa Citizen makes the case:
Using trade-law arguments to force Europe to accept seal-hunt products from Canada, while tempting, could ultimately do more harm than good for trade in general.
Opponents of free-trade agreements have long argued that such agreements have the potential to undermine national sovereignty. By invoking trade law to force seal products on Europe, Canada would be unwittingly strengthening the hand of these anti-traders.
Besides, countries shouldn't have to surrender sovereignty. ... If countries are acting in good faith, they should be able to make ethical and environmental decisions, even if those decisions have trade dimensions.
... Canada should be attempting to change the minds of European politicians, not to force their hands. International trade agreements depend on domestic support; it's never a good idea to give people a reason to be nervous about trade rules, and especially not when Canada and the EU are negotiating a new agreement.
As Prime Minister Stephen Harper has wisely acknowledged, a $7-million industry is not worth poisoning our trade relationship with Europe.
Of course, this assumes that the complaint would be successful, which is still an open question.