It goes a bit further than that - you're asking people to make the shift from a non-monetary transaction to a monetary (quantifiable) transaction. This shift is one-way; once you get people thinking in monetary terms, it's very hard to get them to stop[0].
[0] Of course, you could make the argument that this principle applies on a corporate scale, not just a personal one, which is the point of TFA - Ariely's study just happens to focus on the individual.
Dan Ariely talks about this in Predictably Irrational, and he gives a great example of this involving an Israeli daycare center: http://www.npr.org/2008/03/31/89233955/dan-ariely-takes-on-i...
[0] Of course, you could make the argument that this principle applies on a corporate scale, not just a personal one, which is the point of TFA - Ariely's study just happens to focus on the individual.