Кто везет, на того и накладывают

Everyone takes advantage of an industrious man. See На дураках воду возят (H)

Cf: All lay load (loads) on a willing horse (Br.). All lay the load on the willing horse (Am.). Everyone lays a burden on the willing horse (Am.). If you agree to carry the calf, they'll make you carry the cow (Br.). Make yourself an ass and everyone will lay a sack on you (Am.). The willing horse carries the load (Am.)