Be aware that new GDPR which is European Union data protection regulations coming in will be very strict when it comes to personal data. It also increases risk to everyone who has personal data whether they have it in a email database or as customer information from purchases and locally in a downloaded format.
If you think because you are based in the US or international you wont be affected you are wrong as any persons data from the EU falls under this regulation.
Facebook will become very strict to ensure they will not fall foul of the regulations which means even extracting user profile ID’s might be impacted.
If you dont need to have the data then dont extract it. The fines are going to be very punitive and works out to up to 4% of annual global turnover or €20 Million (whichever is greater).
Personal data is being sold as a commodity especially accurate data like facebook profiles. Be careful with this.