"You sold it to me. If I choose to give that track or album away, there is sod all you can do about it."

No, it's unethical, and it's illegal. You bought one copy of the track or CD, but you didn't buy the copyright to that work. The copyright is still owned by the person who published the work, and only the owner of the copyright may publish copies of the work.

"How many times do you think you're entitled to be paid for one recording that you were happy to make for the pennies that would accrue, and how do you expect to collect?"

The owner of the copyright to the CD is entitled to be paid for every copy of that recording, no matter whether it's an 'official' copy or a bootleg. Not my opinion, the law says so. And making a copy and giving it away denies the copyright owner a sale of the 'official' work.

And we're not talking about the mechanics of the application of copyright law here, merely whether passing-on copies of a recorded work - either FOC, or for barter, or for money, is legal or ethical.