I wasn't dismissing their pain. Many people here (myself included) have struggled with food addiction. I said before that it is not a difference in kind but of degree. Addictions are habits that are reinforced via brain chemistry. I'm not saying that a person can't struggle from trying to cut back on diet soda or cookies. What I'm saying is this: stating that removing sugar from one's diet is the same as removing a daily morphine habit from a junkie's routine is not the same experience.
The biochemical processes involved are different for each, and in that sense it's not by degree- you will not start having seizures when you quit drinking diet sodas like some people do when they quit alcohol; this said yes the pleasure centers are also involved with both and they're the same except that cocaine stimulates the pleasure centers to a greater degree. The study you published indicated that there was a broader amount of neural activation in the case of sweets but this doesn't mean that sweets are more addictive, it just means that there was a wider range of activation, the meaning of which is open to interpretation.