charliehall, are you suggesting that a boy should marry a girl that he finds unattractive because to not do so would be acting like the goyim?!?!?!?
Be realistic, many boys DO find heavier girls unattractive(regardless of whether it is right or wrong, at this point it is a FACT), so…you can either tell them they are acting like the goyim, which will NOT solve the problem, or you can suggest that the girls try to lose some weight which may solve the problem.