It's an infinite sum of variations of the same photon, not an infinite amount of photons. When it hits the detector (or, really, when the researcher eventually

It's an infinite sum of variations of the same photon, not an infinite amount of photons. When it hits the detector (or, really, when the researcher eventually gets entangled with the experiment) it is detected as a single interaction. This is why the terminology is confusing. A "classical" photon just doesn't exist in the modern treatment but we still need it to talk about what we do.