As far as I know, this little piece of software used to be free. Then the users were pretty much sold the product they already had with the pay-what-you-want model. After that, the users were again sold the product they already had after the licenses expired and Mojave conveniently broke the app. Yes, yes, updates require work and there is absolutely no open-source community that would take care of this and all that jazz. Anyway, I only have one question:
How many times are you intending to sell me the same product?