I am one who has indulged in the delights of smoking pot. It affects everyone differently and while it isn't addictive itself, the feeling of being high can be, just as any other feeling can be. An orgasm, feeling safe, feeling adrenaline...
The only way that I can explain my point of view on legalizing weed is this:
When I turned 21, it wasn't all that fun to buy beer anymore. I could, any time I wanted, just go and buy it. I didn't have to smuggle it, I didn't have to pray that I didn't get pulled over with booze in my trunk. It was fun sneaking around to do it.
Same with weed. The thrill in it for me is the sneaky part. A lot of people will likely stop smoking weed when the thrill is gone. It will become more regulated.
But, in all honesty, people with illnesses and pain... they could use weed instead of dangerously addicting narcotics to ease their pain. Get a little buzz and chill out versus being too zonked to operate and having addictions long after their pain has healed from an injury. Just an example, if not a rather rambling one.