The applicability of the spectator model to reactions with weakly bound nuclei is considered by the example of the inclusive proton stripping reaction at deuteron-nucleus diffraction interaction. Analytical methods are used to calculate the integral and differential (with respect to the neutron longitudinal momenta) stripping cross sections. An actual relation is obtained for the effective potentials describing the absorption of each nucleon by the target nucleus in different configuration space regions, which contribute to the stripping cross section.