I don't think it was even that it was rich people.

We recently had the mystery disappearance of Nicola Bulley in the UK that got huge media attention because everyone was playing detective; we've had similar media frenzy over the Chilean miners, the Thai footballers in the cave, the RAF lad who disappeared on a night out (it's thought he climbed into an industrial bin)...

The common thread is that everyone can speculate on whether the subjects will survive or not. 'Migrant boats sinks' stories are focused on too many nameless people and the outcome is too easily predicted for a media frenzy and workplace discussions. People love a bit of speculation.