-Either both miners and node dont get paid = voluntary work in the name of altruism
-Or both get paid = for profit business
You cant mix them, as it is contradictory.
This is a false dichotomy.
When one wants broadband to the home, one requires an access point. This is in addition to the LLC, fibre and all the infrastructure owned by the provider.
Having an access point is a requirement to participate.. They don't pay one for having an access point. The same argument can be made for the required parts of the Bitcoin system and, indeed, it was with the first implementations where one had to have mining, full node and wallet.
So the choice isn't altruism or financial reward, it is a requirement to participate or financial reward for infrastructure support.