In the Wilsonian viewpoint, quantum electrodynamics is an effective theory, where the low energy predictions are obtained by coarse graining eg. some form of lattice QED where the lattice is taken very finely. In the Copenhagen interpretation, we are agnostic as to whether the wave function is real, or for that matter whether observables are real. Only experimental results are real classical events, and theory only gives the probabilities of experimental results. Does the Wilsonian viewpoint require taking the lattice to be real or classical, in the same way that Minkowski spacetime is considered real or classical in special relativistic quantum field theory?