Self cast still allows you to cast on allies

Before season 5, self cast made it so that you could only cast the ability on yourself. Ever since one of the early patches (5.2?) there has been a bug where if you self cast an ability you can still cast it on an ally, making self cast pretty much the exact same thing as normal cast. There was no mention of the change anywhere so I have to assume that it's a bug. I've posted about this on the forums before multiple times and sent a support ticket to riot but have gotten 0 responses and I'm worried I'm the only one who gives a shit. I used to really like the guarantee that my ability wouldn't cast on an ally if I didn't want it to.