Should Advert have age rankings?

For this question I choose to take "Grand Theft Auto" as example because this game is for people who has more than 18 years old, but some people from +14 buy it. This game  should be just for 18+ because children in todays society are very violent and learn how to have a lot of hatred for people. Games have a very big impact on peoples lives because they are roles that people are going to take in their daily life. games are very popular in terms of a lot of people willing to buy games like these. If people under 18 get hold of these games they will be controlled by a lot of violence and this might cause harm in peoples lives.

Parents need to know that Grand Theft Auto V is an M-rated action game brimming with gang violence, nudity, extremely coarse language, and drug and alcohol abuse. It isn't a game for kids. Playing as hardened criminals, players kill not only fellow gangsters but also police officers and innocent civilians using both weapons and vehicles while conducting premeditated crimes, including a particularly disturbing scene involving torture. Women are frequently depicted as sexual objects, with a strip club mini-game allowing players to fondle strippers' bodies, which are nude from the waist up. Players also have the opportunity to make their avatars use marijuana and drink alcohol, both of which impact their perception of the world. None of the main characters in the game makes for a decent role model. All of them are criminals who think of themselves first and others rarely at all. Few games are more clearly targeted to an adult audience.

In my opinion these advert should be for people +18, but if some people will not respect the age raking, I don't think it should have age raking, perhaps only to prevent parents.