To my knowledge, Applesoft BASIC would have been written by Microsoft with some modifications done by Apple. On top of that, it is likely that TASC made calls d

To my knowledge, Applesoft BASIC would have been written by Microsoft with some modifications done by Apple. On top of that, it is likely that TASC made calls directly to the BASIC ROM. Reimplementing bits of BASIC would have used already scarce RAM. Licensing probably made the most sense in this case since little (if any) of the original BASIC code would have been of value and it offered the developer the opportunity to sell their software without publishing it themselves or maintaining the software if they found someone to publish it.