Emails are one thing and can easily be deleted. Cards by Royal Mail are another thing - they are not from RM, just delivered by them. Scammers use the RM because it is trustworthy. Scams basically work on two things: our naivety / lack of knowledge or our desire for money for nothing (greed).
The first group I have some sympathy for, the second - none at all. A lot of people scam themselves as they are gamblers and chancers. Hard lines.
Wise up FFS!