I don't think it's the appropriate means of making sure they're not paying it.
I think we need to take, as best as we can, the Carter commission's recommendation that you tax all forms of income and then provide other mechanisms to ensure that taxes are being levelled where you want them to be levelled. Provide credits as a means for people to reduce their tax burdens rather than leaving this area of certain forms of income that aren't going to get taxed, which then just entices all kinds of deformations of how people are going to operate to avoid having income that gets taxed at all.