How can you compare blank media with something that has data on it?Or should I point to a copy of The muppets on bluray at $30 and claim thats how much a bluray would cost for games ?
How many layers does that 25$ flash card have on it? For one thing it's already without tax if I've understood US laws about online purchasing correctly. Sure, the manufacturer wants some profits, shipping costs something etc but I'm fairly certain you can't get the price <10$ while pressing a BD costs under 1$.
Another thing is about loading stuff to them. Filling up 16G to a flash card at 40MB/s would take ~6 minutes. If you plan to sell 5M games it needs a cumulative time of ~63 years. Obviously you can parallelize this. Say with 1000 machines it will take "only" ~23 days and nights. How much will the infrastructure cost for such a thing?