Hi fishy_fiz, while I agree with your sentiments on piracy, the trouble is neither ebay or any of the companies you mention actually care about old Amiga software.
Simple reason the publishers don't care is they no longer make money from them, although I think they still can if they could be bothered to release some of their old back catalogue as budget releases or on a compilation cd. There not much chance of that though, not enough profit in it for them I reckon.
As for ebay, I've found here in the UK the quickest response you'll get from them when reporting pirated/dodgy/faulty goods is to threaten them with Trading Standards, they soon remove the offending items then.
The thing is and although most won't publicly admit it, these days things like that on ebay or from the numerous dodgy sites on the net, is for most folk the only way they can get hold of this old software.
Guess it's down to the morals of the individual as to just how strongly they agree or disagree with the use of such software.
Wish you luck in your quest, but to be honest I don't think you'll find the response your looking for if any, from ebay or any of those companies...

PS:I'd be willing to bet you've just created a few extra sales for that item, by simply posting the link here...