I agree,I find this irresponsible. If it was her who stole it, great then go ahead. But I highly highly doubt she has anything to do with this, she just bought a laptop for cheap, probably after saving up lots of money, and now all her actions are being posted online for the world to laugh at.

If I had bought stolen property in the UK I'd be in trouble, knowingly or not.

What's to worst they can do to these people? Remote format these devices that aren't really owned by them?

Dom could remote on to steal their bank account information and have them purchase a new macbook for him.

The publicity lets these people know they have stolen goods and they format them to protect themselves from the previous owner.

It is an extraordinary claim to say that they "certainly" did nothing wrong. You don't know that, and just as viable of an explanation (even more seemingly logical) is that this is the family of the thief.

However if we accept your notion that they have "nothing" to do with it, the secondary market is what props up the theft market. Many people buy goods from shady actors and with shady pasts ("Oh I've totally lost every supporting component..."), knowing how the sausage is made. Those people should worry about the goods, and hold some culpability in it.