I believe true "hazing" has no place in basic scuba training, however I do believe that random problem solving practice/training makes stronger divers.
Take the OOA (though this applies to just about any issue)...
When I first was faced with an OOA drill, I was on my knees in a pool and I knew it was coming. What did I learn? Next time, I was on my knees in the open water and I knew it was coming... didn't, learn anything there either. At the end of that series of dives, I was a "certified scuba diver trained in safe diving practices including managing OOA emergencies." If I ever had someone kneeling in front of me while they experience an OOA emergency, I'd be ready... especially if I knew it was coming. Sure, this is a good base, but typically this is where the OOA training ends.
This experience of not feeling truly prepared is what caused me to firmly place myself under the wings of some great mentors... I didn't know what I didn't know, but what I DID know was that there WERE people who knew what I didn't know. (hope you could follow that)
As I progressed in my diving, my wonderful mentors and different instructors started actually teaching me to be a strong diver... not just a "good enough, I guess" diver. Part of my growth included being given "issues," including OOAs or lost-mask or whatever, that I had to solve on the fly. As I became better at solving them, they came in greater complexity... and that still continues today.
A perfectly logical example of how things can go bad in an instant - I could be in Bonaire diving Angel City, reaching for my camera to take a picture of something when my buddy goes OOA and turns quickly to get help, accidently kicking my mask off. Perhaps a bit panicked, he grabs my reg from my mouth while I'm dealing with my mask issue following me not seeing him asking for it (because my mask was kicked off)... now I need a reg, and I can't see yet. I switch to my back-up reg, get a mask on and cleared, and am finally finished dealing with the acute issues that all came out of nowhere. This could happen to anyone, and while everyone (hopefully) who would be diving in Bonaire is "certified," I bet you'd find a whole range of situational outcomes based on the diver's experience.
From my training and mentor's help, I now have the expectation that an OOA, or other emergency/issue, or combination of issues, can come at me anytime, anywhere, under any circumstances, etc. With this expectation, if a buddy "throws an OOA at me," be it real or a drill, I react the same way. My thought process is simply "oh, it's an OOA drill" and I react properly to fix it with little to no stress. "What? It's not a drill this time? Well, it's taken care of so let's start the ascent."
Instead of thinking "OMG!! HE'S OOA!!," I react with little to no stress which makes my reaction much safer, faster, and more effective (it's muscle memory). I do this only because it's something I'm used to having happen so when it comes at me I don't get all excited and stressed. This allows me to manage the situation with a clear head.
In sum, I don't think it's necessary for an instructor to throw as much as they possibly can at a student "just because (hazing)," but I do believe that giving your students an opportunity to learn how to "think on their feet," and teaching them to continue maintaining those skills (to build and keep muscle memory), will make stronger divers at every level.