Links to commercial sites/suppliers are a touchy situation, and it can be tough for a MOD to determine what is spam, and what is a useful and germane inclusion.
I often add links to commercial, or 3rd party sites, but ALWAYS try to point out that something is shareware, freeware, of other. I also make 100% sure that any commercial link is highly germane and hopefully helpful, in solving a problem.
The actions, an interpretationsn by MOD's, will differ, forum to forum, and MOD to MOD.
As a "for instance," it is fairly common for users to recommend a non-Adobe product for DVD authoring in the Premiere Elements forum. While PrE offers limited authoring functions to DVD-Video, or BD, it IS very limited, and there are some programs, from another source, that do a more complete job with regard to authoring. Adobe has never had an issue with such recs. and links, which speaks well of Adobe, in my book. In the end, the user still uses PrE for editing, and then another program for the last step in the process - they are able to then do much more. The MOD there has even published a book on using one of the oft-recommended programs.
So, it just depends, and probably should be viewed on a case-by-case basis.
Not much direct help, regarding your question, but just some observations.
Hunt
