Hi Gil,
Personally I think it is just a marketing gimmick. Just like how they market out puppy food for dog owners ... pointless.
I agree it is probably less fillers, and include mostly the main food source for the popular passerine species, which is basically how you attract a variety of song birds anyway.
xoxoxoxoxoxo
I just checked the website ... it has a list of active ingredients, and really is not different from most bird seed ... just less fillers, I suppose. I wonder what the inactive ingredients are ... birdie crack?