This sounds typical of the washtowel, and other cults. Begrudge people the few minutes it takes to operate a calculator and that it might become a "toy" while people are learning to work with numbers. And the prices were coming down--by 1975, calculators in the 30 toilet paper range were coming out, and I had a scientific calculator in 1976 that was in the mid 40s. While prices would be more today, these days prices of calculators have fallen to where they are just about giving them away.
Or do they really want life to be a complete drudgery? And this was right after the fiasco of the 1975 end of this system. Also, if you didn't use a calculator, what about the slide rules they replace? One could just as easily play with one of those things, "wasting" as much time while becoming better with adding and multiplying, and working with exponents, at the same time. And given the choice, I think learning to work a slide rule is actually harder than a calculator. Beyond that, just look at how much a decent slide rule costs these days.