[coldtea]

>But if you work in the libre community, you'll see that ethics and promotion of the libre is a very important part of it

For how many people? Most major FOSS people I know work in large companies from Red Hat to IBM and Joyent. Heck, speaking of Python, Guido worked for Google and Dropbox.

And most of the others are volunteers.

Besides, I wouldn't call "tripling the price" when you don't like the client using an older version exactly "ethical".

Have you talked to the client? Do you know their costs and externalities for a 2.7 -> 3 rewrite of their existing (and working code)? It's not like they are capricious and want to use 2.7 out of malice.