Kidding Me?

Received the below communication from those lovely folk at The Sun newspaper. Basically to get a free £5 note, I need to register 28 unique codes printed in the daily newspaper. I don't know for sure- I'm not a regular (physical) newspaper reader- but let's assume each copy costs 50p, I'd need to spend £14 (US $18, AU $23) just to get back £5. Is there something I missed..?