Yeah, a bad reason.
https://www.abc.net.au/news/2015-08-10/are-calculators-affec...
> In a 1997 review of the extent to which calculators were being used in schools, numerous studies were examined that indicated the use of calculators at primary levels had no detrimental effects on students' arithmetic abilities.
> Unfortunately, the research indicated that calculators were still being used for trivial things like checking answers and were making little difference in mathematics education.
> Although teachers indicated their support for the use of calculators across all levels of primary school, there was little evidence that these ideas were being taken up and implemented.
> Parental disapproval of the use of calculators was cited as a possible cause of the limited take-up.