So they DO have something to complain about; so what's the beef with them complaining about it? Because they're not using your perspective? You're complaining that they're not looking at the issue through the perspective of others, so aren't you doing the same thing?
The life experiences of people on the other side of the planet isn't more tangible than your relatives' life experiences which have borne witness to the suckiness that you acknowledge they've experienced. If a parent loses one child in a car accident, are you going to tell him to "stfu" because another parent somewhere lost two children in a car accident?
[1] https://www.forbes.com/sites/timworstall/2013/06/01/astonish...
[2]https://www.quora.com/What-are-some-examples-of-dark-humour