To be fair, the extension "ads" as you say are just images with links, they do not track you... also if you do check the registration screen clicking "steal" or use the console command there steal(); on register.html is a valid option for registration and disabling the in page "ads" with the advanced option.

These amazon affiliate links, nor the actual ads on the website (which is not really something to review here, imo), have ever made an appreciable amount, hosting costs more than has ever been acclimated by any means, including registrations.

I wonder how the alternatives stay in business, just saying... because there ARE unethical ways to make money on extensions, but this extension does not do that.