Yes smurf is definitely bad but there is no way to avoid it, specially with free 2 play. Not to mention SC2 have a great system to make smurfs get quickly to their leagues which is provisional MMR in the first 25 games of the account. The good thing is that it doesn’t take long for the smurf to go above your league.
IMO Barcoding is even worse than smurfing but there is no way to avoid it.