See, I don't mind sending money. I don't see it as trolling, I mean, they must genuinely need it to bother posting, even if they are exaggerating about having eaten cat food to survive.
Really?
You realise that there are people who make accounts on popular websites just to befriend the naive, and make money don't you?
On normal sites, they'll put a few months of posting in...being nice to everyone and gaining trust...so they have a posting history before they strike with the sob story. This is called 'puppy walking' the account.
It only takes a handful of people on each of those websites, to send them a few quid and it makes it worthwhile.
Mumsnet however, must be the easiest site around for these people because due to name changing (banned on most other sites) they don't even have to build up a history...they can just say they've name changed because they're embarrassed.
Now you might be thinking this is far too much trouble for some people to go to, but they treat it like 'working from home'. Knowing they get to chat on the internet and by Christmas they should see a financial gain.