Yes, I have parents in law just like that. They have only 2 sons. One is the older brother and the other is my husband. I literally heard them (I was in absolute shock, because my family is very close knit and would never say let alone think of anything like this) both his father and mother, say this to our family in disdain when talking to his older brother -quote, "I do not want them to get rich through us".
Yet they are happy for the older brother's family to get rich through them. I don't understand. I'm still in shock to be honest. I don't know what to make of it as it is so far removed from the attitudes of my loving family.