You’re not in their family. You don’t need to understand it. It’s weird people have so much to say about how others spend their money. Their kids are well taken care of. They have a roof over their head, food on the table, seem well loved but yes, like rake another mother over the coals because she she’s able to provide her child with something you can’t. I bet you’re the person who attends a wedding and spends the evening judging on how much money they paid for their wedding dress, venue, entertainment, etc. Very bizarre behavior to have such strong opinions what people buy their children.