Once in a while, I do not think that it is bad to work the works you mentioned and sustain study. Even in Nepal, people who come to KTM from outside works during study. But yes, if anone has mentality to work in Gas Station and restuarant even after achieving Degree, just trying to stick in USA anyhow then that is different matter. Regarding DV, I too have some Engineer friends who had DV lotter, came here worked at Subways till got settled or got better engineering job. Its matter of luck for now. Thats all.