Especially if you're a journalist who has an alternative line in PR and email marketing...
If you receive a piece of email that has 252 people in the CC line, it's absolutely fine to mail back and point out that this is poor email etiquette. It's a great opportunity to pitch your email marketing services to someone who obviously needs them. But if you're going to suggest that it's a grey area for data protection and you also plan to include screenshots of your service in action complete with screenshots of a report for a previous project - perhaps you want to go delete those 251 other people in the CC line, or just not hit Reply All in the first place.
Just a thought...
