All the stored procedure programming languages of commercial SQL servers, .NET before Microsoft opened it up, commercial compilers of Common Lisp, C++ Builder, Delphi, Ada, C and C++ compilers for embedded development (no clang and gcc aren't the only ones), Coldfusion, Flash, Objective-C (gcc and clang are just a tiny part of the whole stack), Cobol, RPG, NEWP, a few in-house proprietary languages, Java compilers for embedded platforms with extended AOT features
It doesn't matter if there are open source implementations of language X, if you cannot use them in processor X, operating system Y, rather the closed source commercial compiler of the processor X, operating system Y vendor.
What they care is who support their tools, who they are going to call, how SLAs are enforced.