Last time I agreed to Facebooks terms of services it explicitly said that the agreement is between me and Facebook Ireland Limited in Dublin. I only ever consented to the data being transferred and processed in the US.

The Facebook Europeans use is very much an EU company.

I believe McDonalds locations inside Europe do follow EU laws, so yes.

You seem to not understand the difference in location. Of course companies in the EU follow EU laws.

And FB has presence in the EU.

Very limited and if the EU will keep fining them, they will leave - and that will mean the exact opposite of what EU wanta because not having an EU entity doesn't mean they don't continue to have EU users.