This is obviously a consequence of the clever tax avoidance schemes companies like Facebook have used to minimise local revenue. Fining an international corporation based on the local revenue is pointless when the corporation can shift numbers around to turn that revenue into close to nothing.

You think Facebook is going to start charging fees to people in the US to pay for fines from the EU? Well I heard that if this post gets 1000 likes Zuckerberg will cancel his plans to charge for Facebook.

(It's also arguable that greater privacy protections are to the benefit of everyone, unless Facebook only enables in them in the EU)

So you think the EU doesn't account for more than 4% of their worldwide revenue? It's not like the fine is for 100%.