A world without opportunity costs?

From Question Time yesterday comes a useful question for anyone setting Principles-level exams. Discuss this exchange with reference to theory as discussed in class. 

Hon Amy Adams: How can he say that he's used "evidence and expert advice to tell us where we could make the greatest difference to the well-being of New Zealanders", when the Government has chosen to pour hundreds of millions of dollars into fees-free tertiary at the expense of giving Pharmac enough money to keep pace with inflation?

Hon GRANT ROBERTSON: The premise of that member's question is incorrect. Money that supports education, money that supports health, and money that supports housing are all part of the Budget; one is not at the expense of the other. What we're doing is actually making up for the enormous under-investment of the previous Government.

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Hon Amy Adams: Why was spending $7 million on Artists in Schools a higher well-being priority than the mere $6.5 million needed to reinstate cochlear implant funding that his Government cut in last year's Budget?

Hon GRANT ROBERTSON: Again, the member is not reflecting the Budget process that she knows well. These things are not trade-offs against one another. We are creating an environment in which we're investing in well-being across all sectors of the economy. In the health sector, this Government has a record that is far superior to that Government.

Robertson could be right if they just set a total amount that will go to health, then weigh bids within health against other bids within health - but that would also make a bit of a nonsense that the wellbeing budget ensures every dollar provides the greatest possible increment in wellbeing.