Why do they make sleepers so long and skinny?

Are the makers of toddler's sleepers trying to give my daughter a complex already? Why do they make the things so long and skinny? Typically I buy Carter's pjs but since I can't find size 18 months ANYWHERE, I bought some at the Children's Place. I had to cram her leg into her new jammies and be very careful not to zip up her leg in it! The reason this frustrates me brings me to tip #1. For those of you who are working moms trying to get yourself and your child(ren) ready for daycare in the morning, you understand that every last minute of time is needed. I always dress Emmy is whatever onesie she is going to wear to daycare the night before so all I have to do in the morning is put pants on. Yes, that means she still wears a lot of onesie but it is so much easier. So, when they make the damn pajamas so tight it is hard to fit some of the onesies under them! So, let me know if you know of a brand of pjs that is made for a normal sized child, not a bean pole.