Although I worded the OP semi-seriously (by including a reference to overweight), the question is a relevant one. Sometimes I offer a rov a ride, and his rebbetzin discourages him from accepting since she wants him to gain the health benefits of walking. (He is not overweight but he is elderly.)
So, often, when seeing someone enjoying a walk to the commercial avenue, in the same direction I am headed, I wonder if I am helping or hindering by offering a ride. (And if I ask, he may be reluctant to decline even if he’d prefer to walk.)