Nitpick: an individual or entity with $100,000 in revenue per year cannot publish using the free version. Per their license[1], it does not matter where the revenue comes from. There is probably some sort of legal gymnastics you can perform to get around this, and one could argue that if you have $100k in revenue you shouldn't be worrying about a $1500 one-time purchase, but it is a limitation.
[1] http://unity3d.com/company/legal/eula