they are trying to sell you something so they are going to say that. i have run 3 inch lifts on two 87 model jeeps with control arm front ends, the xj and the mj. i have also run 3 inch lifts on two or three zj grand cherokees, which run the exact same front end as the xj and mj jeeps (and the tj wrangler, in case you need parts sometime).
3 inches and lower do not require a drop pitman arm, adjustable control arms, or track bar. you can, if you wish, but its not required at such a small lift
and, if you don't want to do control arms, they also make control arm drop brackets, which lower the mounting points at the frame. some people like them, and some people do not. i have used them and i have used adjustable control arms. i like the brackets more because the ride is a lot smoother, but i am talking on 5 inch lifts, not 3 inch