I do not think that it will be an issue. My Parents and inlaws visited me when I was in F1 and then when I was in H1 and recently when I am in EAD stage. I did not sponsor any of them. They applied for tourist visas and explained that they wanted to visit their son or daughter. Even my brother, who is in his 20s and single visited me twice during these periods. I think that as long as the immigration officer believes that the person is going to return to his/her home country, they grant the visa. Questions will be raised and sometimes visas will be denied if there is any doubt regarding the intention of the visitor.
