Groupon, Restaurant.com, Uber, Uber Eats, Grubhub, DoorDash, Lyft, et al. What's their cut from the service provider, say a restaurant for the delivery service or the drivers and their cars, like? What's the cut from the Consumer like? What tricks at play to attract and keep both?
If you could create a mesh network / block chain version of those businesses you could presumably wipe them out. Airbnb as well. Also Amazon really