I personally don't believe parents "need" to have control over children. I try to respect my child's opinion and take that into consideration at all times, I always strive to treat them as I would anyone else, and I would never try to control another adult! My children listen to me not only because they respect me and my opinions but also because they know that I always will try to take their opinions into consideration and find a mutually agreeable option that everyone can live with.
Since you simply 'take into consideration' your child's opinions you have control. If your child was the one who made decisions after considering your opinion they would be the one in control. If your child's opinion was that they should be allowed to color all over the walls and you said no you would be controlling them. I admit that it's an odd way to think about parenting but I do think that it's control nonetheless.