What's the deal with meta advertising?

I don't watch T.V very often, but do - when I'm up (which is infrequent given I'm outside the U.S) - watch the NBA. Recently I've had a little time so have watched a few games live. Doing so, I was quite taken aback at how commonplace humour and meta advertising are nowadays. Is this just a U.S thing?

Is there any research out there on when and why advertisers started doing this? Seems like every other ad shoots for either humour or "we know you know this is an ad, you're clearly smart enough to realise that, so smart in fact you might want to buy into our brand". Whatever the case, as ever, grateful for resources/discussion from those more in the know than I.

EDIT: A good example that is equal parts humour/meta is LeBron James' Super Bowl Sprite Ad.