Why does Botox and Juvederm cost significantly less in the UK?

The price of services is always proportional to the living standards of the area where the office is located. Even within the US you will find higher prices in Los Angeles and New York, in comparison to smaller towns in different areas. Providers pay different price for fillers since pharmaceutical market price of the same product differs for different regions.

Corporate greed.  Allergan works with FDA to make  sure that rather than having 80+ fillers available to us as in Europe, there will be only handful of choices in US.  This is so they can increase price for the products and cost to physicians and consumers.  Rest of the world operates in free market but not in US.