At the I-70/T. R. Hughes Boulevard/Belleau Creek Road SPUI in O' Fallon, MO there is a signed U-turn for eastbound traffic through the SPUI (https://goo.gl/maps/kuoc4K3MRGsQS2419). Is this a one of a kind thing or is this more common in other states?
It looks like a special case to serve the special purpose of showing traffic on the eastbound offramp how to access "Terra Lane", the surface street only accessible by way of the westbound onramp. Terra Lane is a frontage road along the north side of I-70, and it's lined by businesses that I-70 traffic will seek to access. I think that's the main reason for the sign posted here. It's just like the Texas system of one-way frontage roads that hug either side of their freeways--if a car on I-20 eastbound wants to get to a hotel on the north side of I-20, for example, it needs to exit just east of the hotel and use a U-turn to get to the northern frontage road. Texas will install channelized U-turn facilities to assist in this commonly-I'm not sure if Texas has any SPUIs like the example you provided...but if they did, they would have to allow for U-turns! The weird thing here, I think, is the frontage road accessible only via the SPUI's onramp.