In my opinion, I don't see the pros. Baby contests are different because they are just babies who don't know any better and their little minds don't get what's going on. But these older children whose appearance you have to physically alter, I am against.
There is no such thing as a pageant that you can enter that goes by your natural beauty, where you are not allowed makeup. And if there was, it would be heart breaking because not everybody will think you are pretty. Can you imagine losing because you are not pretty enough? How do the losers feel?
These children are made to wear tons of makeup, dye their hair, fake hair, and fake teeth. They wear these plastic mouth guards resembling the kind you wear kickboxing because their natural teeth are not even, (and some have baby teeth, some are missing), and not considered attractive. "Sorry honey, your teeth are missing, let's put this big plastic mouth full of fake teeth on so you can be prettier. Now for your hair..."
Can you imagine what this little girl is thinking, feeling about herself? She trusts her parents to guide her, so she isn't thinking for herself at all. I don't buy that crap about how they like it. They wouldn't have known about it unless you taught them.
Their audience includes pedophiles and their moms are only too happy to expose their photos on the internet.
Where is the pro there? The money the parents make or the trophies? The "fame"? These children are learning the value of winning at the cost of their childhood, morality and self respect.