Over charging

Today I went to baby boom to purchase a few things , I got baby formula nappies , bottles etc. they didn't have to pram I wanted, so I decided to go get one at baby city. While walking around I saw the Nan HA which I had a look at the price, to my surprise it was R60 cheaper at baby city then at baby boom. Baby boom was R199 and baby city was R139. I am highly disgusted that you can over charge. I am a new mom and have just put my baby on formula. I will never shop at baby boom again , I will there for spread the word to all moms