You're sounding very confident, so I'm guessing you have a source for that claim?
Besides, even if 90% of the API usage is for scraping and does not impact the bottomline, it's still a smart business decision to leave the API open if the remaining 10% are for posting content that brings in views and thus ad impressions that generate more money than the API costs to run.
That shouldn't be possible, API request limits for 3rd party keys were greatly reduced in 2018 to less than what is available for 1st party clients. Extracted 1st party keys or Web scraping would be used for that purpose.