One of my outlaws gripes about any penny he spends for his kids medical care, and goes on a rant about Obamacare every time no matter how small the medical bill. I always bite my tongue (and this has nothing to do with Obamacare per se) because they spend money like they must have a $5 to $10 million net worth. Seriously, they have a big house with a pool in an expensive suburb, three luxury cars and a boat. Money constantly goes out their door for frivolous things. Then he gripes because of a $1k emergency room visit that saved his kid's finger. I'd be happy the bill was just $1k so long as my kid was ok. He even gripes about a little copay for antibiotics when the kids are sick. I'd like to throw all of his wasteful and extravagant spending back in his face the next time he complains about what, at his income, must truly be a minor expense.
Gotta keep the peace in the family.
Edit to add this thought: I hope the bro-in-law is quiet about this at his work. His coworkers probably, and his boss certainly, know his salary and his benefits. And they've probably seen what he drives and are familiar with the community where he lives. If he complains that he can't pay for basic family necessities, it's going to imply that he can't manage money. This is not a good image to have if he wants a promotion.