We take fire for granted. All we have to do is turn a knob, set a thermostat, strike a match, or flick a BIC.
Man has been in control of fire for a long time. Some scientists seem to think from the artifacts that man has been using fire for cooking, warmth, light, and fellowship since 1.9 million years ago. But, I bet they had a harder time starting fires back then since they didn't have any BICs or Zippos or even matches.
Probably the first fire that man made use of was started by lightning strikes. Once they had possession of fire, I am sure that they did their best to keep it going day and night so they wouldn't have to wait until the invention of the match to light another one. . . (grin).
I don't think that a fire for them was just for fun. It was a matter of life or death. Not only would they cook over it, they would use it to warm themselves, to give them light in the night, to deter wild creatures, and maybe to sit around and tell ghost stories. . . or maybe not. But I bet they told it over and over how they chased down and killed the animal that was feeding them at the moment.
Yes, I am sure that they ate a lot of their meat raw, but they were quick to learn the art of cooking. They didn't have a McDonalds close by to run to when they were hungry. Maybe it is a throw-back to those times, but I prefer my steaks rare to medium rare. Well, no matter how you like your steaks, or if you are a vegetarian like my wife, I want all of you to have a great day, you hear?