If you can not drink and drive, why you need a driver’s license when you buy an

because you need the license to prove that you are 21 years of ages, other wise everyone would go in there and since they make it aginst the law for under 21 to drink that is why you need a driver's license when you go into a night club because you need to be 21

A drivers license is commonly used as a form of ID....your often asked for it if entering a nightclub purely for the fact it has your date of birth on it and a picture. Its something that most people carry with them all the time as it is usually kept in their waller/purse. There are other forms of ID that will get you into nightclubs though.

You don't need a driver's license. You only need something to prove you are legally old enough to drink.

In a lot of countries a drivers licence is an acceptable form of ID, but not usually here where I live.