"What's wrong with a charity or an organisation working for a charity wanting to offset some of their costs?"
For a start, I & G Cohen are in this for profit. That's fair, that's business, that's life.
http://www.igcohen.com/But considering they are raising money from a product that has been freely given, for which they offer a small reward for use of the respective charity's name, they do very well.
The Bird does a bit of work in British Heart Foundation, one job is to bag up items that will not sell in the shop, just because they are soiled or a button missing etc. She has to bag up then weigh the bags for collection. Each bag is about 20kg. At £50 per tonne, that's 50 sacks. £1 per sack.
Consider the mark up on the products when Mr Cohen sells the items to traders etc, I think he does nicely, thank you.
But he still wants you to give him more money via the 0870, when you choose to inform him that you have a bag for collection from which he will make further money. Beat him at his own game. The contact number for Cohen is 0161 736 8899, but then could you trust him to make the appropriate donation.
And if you still consider it OK for charities to find other unorthodox ways of making money, remember that it wasn't long ago that it was revealed that The Red Cross movement had shares in munition firms. Now that's a way to keep your organisation employed!