This is also an issue that is becoming very common around my hometown.
The excuse is always avoiding bad influences that can lead to trouble yada, yada.
My thinking is the kid is going to have to experience the world someday so trying to overprotect him now will only result in shock later on. The kid has to display where his loyalty lies and if he really is faithful to God. Parents trying to ingrain a belief or doctrine into someone who doesn't except it or believe it is useless to God. So therefore, protecting a child who is encouraged to make the biggest decision of his life in baptism while still a preteen or teen, yet is unable to care for himself spiritually. Makes sense?
I see the similarity in teaching a kid at home in a driving simulator how to drive. Once the kid passes the driving tests and hits the road he will be shocked to actually experience the true nature and emotions that come with driving a 3000 lb vehicle around other real cars, trucks, buses, trains, bikes, mopeds, and people. It's just not the same.