The idea that AR-15 or AK-47 family weapons are "the same as a hunting rifle, they just look different" is laughable.
Because they were developed from military rifles, AR-15 and AK-47 family weapons are designed to accept a wide range of tactical accessories designed for combat situations. These include high capacity magazines, combat slings, bipods/tripods, bump stocks, etc, etc. Yes, you could in theory manufacture your own for another semi-automatic rifle, but that's a far cry from the huge volume of easily purchasable military grade hardware available with 3 clicks on the internet or in a shop.
Because they were developed from military rifles the AR/AK family are designed to be weapons that can be fired rapidly and in large volume over an extended time. They are very light (especially the AR family), have little recoil, are easy to maneuver, and can be fired for extended stretches which would be nearly impossible with a standard hunting rifle. In particular, the receivers and barrels are designed for a volume of fire that a standard semi-auto rifle for hunting or sports purposes never has to support.
Both the AR and AK families are traditionally chambered for rounds that have little purpose outside of combat. The NATO 5.56x45mm used by the AR family and the 7.62x39mm used by the AK family are both designed for combat situations and ranges against human targets. They are relatively under performing as hunting rounds and aren't optimized for sports either. The 5.56x45mm in particular lacks punch against anything larger than a human, and is a round that was designed to be as small as possible while still being lethal to humans (so soldiers could carry as much ammunition as possible and to limit recoil allowing for more extended periods of accurate fire).
The AR/AK family rifles are combat rifles. They are very, very, very good combat rifles proven on the field of battle over and over. They are optimized for the task of killing human beings, and very little else. The idea that they are the equivalent of a .30-.30 chambered deer rifle is fucking laughable and insulting.