1) Of course there's the standard random luck argument that natural forces just ended up looking like that.

2) Also, the shapes interpreted as Jesus or Mary look like Renaissance era interpretations of what they looked like, but no one really knows their appearance. These could just be images of any random person from history. Do you worship random people from history?

3) With all the power an omnipotent God has he doesn't need burnt toast.

4) If a humanoid outline truly is the work of God then any other shape that might appear, whether it be a frog or phallus or boobs, also must be miracles from God trying to tell us something.

5) If other entities (like Satan) also can mislead with images on burnt toast then how do you know the Mary shape isn't just Satan putting a false idol out there for you to sin and make a fool out of yourself worshipping?

Satan is an imitator. The Fatima story is one of 'miraculous" events involving three little girls which gained worldwide fame, and the whole thing is just a trick of the devil from Hell.

Agreed. Just like percieved holy images of experimental data (or what we believe to be such), do not prove the miraculous fairy tales of modern cosmology.

You hear about these incidences a few time a year in my area and almost always it's Mexicans who see a virgin Mary in a taco, cactus, water stain etc. I think it's hilarious how some turn it into a money making enterprise, charging admission to the gullible to see it. Capitalism, it does a bank account good.