An interesting example of logical confusion in a well meaning campaign. Asda has stopped selling shark meat after a campaign over the possible extinction of certain species:

Tanya Streeter, five times world free diving champion, and a spokesman for Bite-Back, said: “Today’s news sends a clear signal that consumers believe sharks belong in the oceans and not on the dinner table.”

Well, no dear, this decision doesn’t actually show that you have convinced a single consumer of anything at all. It shows that you’ve convinced a retailer, rather a different matter. How do I know this?

Until last week, Asda was the last major supermarket chain to stock shark, selling 100,000 portions of mako and bigeye thresher shark each year.

See, the consumers were indeed biting back and happily munching their way through Jaws and cousins. It is much easier to convince one retailer than it is to convince 100,000 (not adjusting for the fact that presumably some consumers would eat it multiple times a year) consumers of anything. That is why the NGOs go for the supply chain, not the individuals.
What you’ve actually done is reduced the freedom of consumers by brow beating a supplier. As it happens I sort of agree with the aim but I don’t agree with the logical confusion you’re caught up in. I’m all in favour of you putting your message to the consumer and allowing them to make up their minds based on your presentation, and not in favour of your restriction of their choices by beating up on a supermarket chain.