Most of the requirements for a game programming job I've looked at required good C/C++ skills. I agree, most game engines are written in C/C++. But aren't the engines USED in a scripting languages? Don't the companies need scripting programmers to actually code the game from the game engine?
Why haven't I ever seen a company that requires good Python skills? Or do most companies just make their own engines?
I imagine it's because game programming is some of the most skilled work in the industry, and a developed skill in C++ proves a good understanding of core principals of computing, and how computers actually work on a lower level which is essential for game projects on a mammoth scale in a performance crucial environment.
I think you answered your own question. "most game engines are written in C/C++".
Generally programmers who can program in C/C++ can easily program in scripting languages. Therefore, a game company is going to look for an employee who can do everything, not a employee who is limited to just scripting languages.
In other words, learn your C/C++ if you want to program games. :)
How many games actually use python code? Chances are, you mostly read requirements by the big companies, as the small ones hire much less. And the big companies have their own engines which are probably decades old and 99% in C/C++.
Also, if you you have a good C/C++ programmer, he can work on the engine and is likely to learn any other language if needed.
If asking for "pure" python programmers you are likely to get the scripting guys in the boat who are not seasoned C/C++ programmers, and developing these skills will take much longer.
The games industry is so competitive, so they pick the best, so why not ask for top skills like C/C++? I know someone who got a job at Rockstar by writing a small game (think it was a fps, not sure) in C or C++ in a couple of days and he still started as a level designer using GTA's own scripting language.
The engine is not the only component of a game that would be written in C/C++. The actual Gameplay, Tools, Server components (ex. Battle.Net) all could be written in C/C++ and they usually are.
Note, that scripting languages such as (Lua, Actionscript, etc...) are still used and are absolutely beneficial to know. Browsing through the various Software Engineer positions at Blizzard will show that C/C++ is a requirement for all, but you will also notice that almost all of them also consider knowledge of a scripting language to be a Plus for your resume.