You say that, but it's only true to an extent. Pretty much all of the "free" products have a full-price "suite" you can buy and which has the "commercial backing". You also have the full helldesk experience too, if you want. The free ones also have full online help and, in some cases, phone support too. You see, most of the "free" stuff is being sent out as a loss-leader in the hope you like the product and pay for the "full" version, it can have the same backup, etc, and "response time", "r&d", etc as a "full price" version.
So, to try and say that you somehow have a "better" product because you paid through the nose for it is, at best, naive and, at worst, a downright lie, especially as the Avira product you mention is also a fully-functioning FREE antivirus. Oh, it also depends on the reviews as they are all different so you cannot make your claim regarding the "top 3" like you have done.
Oh, please don't try to insult our intelligence by saying Symantec is not Norton is not Symantec, etc, etc, etc. They are the same company and, for the purposes of most of the people here, "Norton by Symantec" (indeed, many reviews state the full name as "Symantec Norton blahblahblah") is the product they will use as they do not need "endpoint protection" and, in all honesty, that hasn't had the best reviews, especially for something that can cost $500+.