"ALCOHOL" VS "INDIAN SOCIETY"

In my opinion most of  the "teens" have some experience with the alcohol  by the age of "17" (under-age drinking).
   This guys are labbeled as perverts and boozers by old
    generations.   
   phys-cos .But i say what the difference does it makes if a 
   person(who is above 18) is  capable of handling it .But this doesn't
   mean's i am supporting anything evil ( i am totally against 
    drunken driving and brawls ).All i want to say is our society is
   headed by-
   past-generation "phys-cos" and they think it's not our culture to
   drink liquor(alcohol) which i think is a "rubbish thought" and if 
   you are opposing their views then they just label you as a 
   "traitor"(i.e traitor of the society).

What's wrong in drinking alcohol if a guy is able to handle it ?
What's wrong in drinking alcohol if a girl is able to handle it ?


p.s- I don't support underage drinking however once i was also a underage drinker and i regret it.the point i am trying to make is if "18yrs" is the legal to join army,civil services or caste vote .So,
why does the society  thinks we are still "amateur" when it comes to alcohol??why??.