  This paper studies finite volume schemes for scalar hyperbolic conservation
laws on evolving hypersurfaces of $\mathbb{R}^3$. We compare theoretical
schemes assuming knowledge of all geometric quantities to (practical) schemes
defined on moving polyhedra approximating the surface. For the former schemes
error estimates have already been proven, but the implementation of such
schemes is not feasible for complex geometries. The latter schemes, in
contrast, only require (easily) computable geometric quantities and are thus
more useful for actual computations. We prove that the difference between
approximate solutions defined by the respective families of schemes is of the
order of the mesh width. In particular, the practical scheme converges to the
entropy solution with the same rate as the theoretical one. Numerical
experiments show that the proven order of convergence is optimal.
