You, along with many others, are oversimplifying this. "Little Johnny" doesn't actually make anything from income sprinkling. For a child to be eligible to receive a dividend, they have to the age of majority (ie. able to legally work). Furthermore, the benefit of sprinkling the money out starts to decrease as it increases in amount. Also, this is a relatively small piece of the pie, as there is generally a limited window where it makes sense for the adult child to accept this type of dividend (as soon as the child is independent, they would be paying more tax to help defer tax for their parents - ie, they wouldn't do this).

Also, the whole concept of doing away with prof corps is ignoring everything that goes into being a dentist or doctor. I graduated from dental school after 9 years of post-secondary education and with $150,000 in student debt (I was on the low end, by about $100,000 because I worked my but off at summer jobs). Thus, we assume massive financial risk, and stress.