Comment by Joker_vD

Yep. Strategy Letter V by Joel Spolsky (2002): "Smart companies try to commoditize their products' complements". Also, from the 2004's "How Microsoft Lost the API War":

    The logical conclusion of this is that if you’re trying to sell operating systems,
    the most important thing to do is make software developers want to develop software
    for your operating system. That’s why Steve Ballmer was jumping around the stage
    shouting “Developers, developers, developers, developers.” It’s so important for
    Microsoft that the only reason they don’t outright give away development tools for
    Windows is because they don’t want to inadvertently cut off the oxygen to competitive
    development tools vendors (well, those that are left) because having a variety of
    development tools available for their platform makes it that much more attractive to
    developers. But they really want to give away the development tools. Through their
    Empower ISV program you can get five complete sets of MSDN Universal (otherwise known
    as “basically every Microsoft product except Flight Simulator“) for about $375.
    Command line compilers for the .NET languages are included with the free .NET
    runtime... also free. The C++ compiler is now free. Anything to encourage developers
    to build for the .NET platform, and holding just short of wiping out companies like
    Borland.

Similar logic applies to selling FPGAs.