@LuGar : I don't and never will have a huge amount since I primarily only buy ones I want to wear anyway, and if I had my way I'd wear the two pairs of "collectible" ones I have now, my wife is the one who is against it.
I had forgotten I do have a couple of items which combine the sneakers/Transformers thing. A few years back there were a pair of Calvin "Megatron" Johnson themed sneakers which came with an exclusive Megatron toy and then there were two Transformers which change into Nike Free sneakers, guess those count toward both collections.