Sounds like more of a genetic issue. Your hip/glute structure may just be a little wider for your overall structure and working the leggs hard just brings it out.
Another situation may be your own perspective on your ass. It may look wide to YOU but to someone else it may look perfectly balanced with the rest of your physique.
Post a pic of your ass and we`ll all, in our honest opinions, let you know if you have a yummy ass or not, LOL
I personally cannot say a damn thing against squats or heavy leg training in general.
Squatting has done me justice because way back in the day I was assless. Yup.... no ass, nadda, zip, zero. I have been squatting, hacking and dead`n for over 20 years and am told by the ladies I have a beautiful ass. What more can one ask for ?