So how does this play out for large companies? Let's say Alphabet, they pay $60 once per month, no many how many of their developers use the product? Probably large companies should introduce some sort of registry to keep track of this.

This is something companies track. Honestly, tracking payments is one of the most important tasks for the procurement teams in a company. They have tools and if the OSMF becomes common, it'll be standard practices for them too.