Universal scaling exponents in shell models of turbulence: Viscous effects are finite-size corrections to scaling

In a series of recent works it was proposed that shell models of turbulence exhibit inertial range scaling exponents that depend on the nature of the dissipative mechanism. If true, and if one could imply a similar phenomenon to Navier-Stokes turbulence, this finding would cast strong doubts on the universality of scaling in turbulence. In this Letter we propose that these ``nonuniversalities'' are just corrections to scaling that disappear when the Reynolds number goes to infinity.