"Santa was very cross. It was Christmas Eve and nothing was going right. The elves were complaining about not getting paid overtime. The reindeer had been drinking all afternoon and the sleigh was broken. Santa was furious.
‘I can’t believe it!’ he yells. ‘I’ve got to deliver millions of presents all over the world in just a few hours – all of my reindeer are drunk, the elves are on strike and I don’t even have a Christmas tree! I sent that stupid little angel to find one hours ago! What am I going to do?’
Just then, the little angel opens the front door and steps in from the snowy night, dragging a Christmas tree. ‘Oi Fatty!’ she says. ‘Where d’you want me to stick this?’
And thus the tradition of angels atop the Christmas trees came to pass..."
Personally, given my week so far regarding Christmas, I would have done more than shove the Xmas tree up the Angels backside. But then, that's just me. DH thinks IBU, because the Angel had done what she'd been asked to do...