I agree, it just may do that, but that brings up a thought I had last year, and still do... Why doesn't the added earth scent, woodland scent, etc. get neutralized in the commercial brands as well? I'm sure it has to do with chemical reactions somehow, but it's just a thought.
I've found the earth scent fabric softeners have no scent after I dry my clothes that have just been washed with baking soda. (kind of unfortunate because I like that scent!) There might be a ratio of baking soda to earth scent that they use or are substituting something else for the baking soda.