It's a lifestyle choice and, as long as it isn't harming anyone else, no-one has the right to ridicule or make snide remarks about people who make that choice.
I see a surprising amount of intolerance coming from a people who originally built their reputation on the back of tolerance and acceptance.
Have you ever thought that it is perhaps this exact kind of scolding and stuck-up attitude towards "how it should be" that is driving people away - if, of course, that is the case.
I do not agree with you.
Let us take the case of members of associations like, professionals, Doctors, Accountants, Lawyers or political parties. Every association has its rules and regulation. Its members have to abide by the ethics prescribed by the concerned association. If any member breaches it he has to apologize and amend his future actions and if his action could not be condoned he is expelled from that association.
Likewise when a Sikh cuts his hair he is declared a PATIT and excommunicated from the Panth. If he trims or shaves partially he is asked by his elders or near and dears to abide by Sikh Maryada.
It is not any type scolding which drives one to shaving off his hair. Either he has fallen in bad company or he has seen some one shaving off and nobody criticized him or he had to face any sort of hardships like snide remarks or ridiculed by others and, thus he got encouraged. In Sikh households it should be made clear to the children that the family is not going to tolerate anything like what so and so has done(shaved off hair) and that person shall be denounced whenever his name crops up in discussions.
In a few lines I will tell my story. In Burma, where I lived, during end of II World War one Sikh, a Government official, said that times are changing fast. We used to greet each other with salutation "Wahe Guru Ji Ka Khalsa Wahe Guru Ji Ki Fateh", but now people greet each other by salutation with a finger. Times are changing, before we used to travel on foot, cart or cycles. Now by cars and air planes. By the time we say "Wahe Guru Ji........." the man greeted is far out of hearing. Sikhs will shed their hairs and there will be no Sikh by end of the century.
Hearing this I pledged that in such a situation I would be the last Sikh living in my Sikhi form. My son some day heard this episode when he was about 7-8 years and he now says he will be the last Sikh living should this impossible situation arises.