Local Fox Outlet does these Deal or Dud stories and he covered 4 of the local portrait studio packages and points out the fine print.
http://www.myfoxdfw.com/myfox/pages/...Y&pageId=3.6.1
What is interesting is that it looks like Wallmart may be using this as a loss leader to get more people through the door since the $9.98 charge (+tax) covers little more than the print costs of the pictures offered. So they really either push people to buy other items with their pic on it or they may tell the people to come back in X minutes to pic up their photos so spend that time shopping.
One of the poses chosen by one of the photographers to me made the youngest child look like he was dead and another was just plain terrible with the kids looking like they were told "climb up there and do what you want".