Popa, you’re putting a very positive spin on it, but I don’t think that they’re being so profound.
If I were to put a positive spin on it, I would say that it’s simply because she wants the z’chus of financially supporting his learning. My cynical side tells me that it’s so she can boast of her husband in kollel (which isn’t the worst thing someone can boast about).
There’s probably some truth to both (maybe even all three).