I've sat in the right seat during a couple of demos which I've enjoyed from our local examiner, and my PPL instructor has had me flying wing overs and aileron rolls for "a bit of fun" relatively early in my training.
GREAT FUN !!!
For a newbie it is a great way of knowing and seeing what a plane can do - so as not to be scared of it - and see something to aim for (aspire to) way off in the future.
Very interesting also to see the difference between doing it to enjoy (build up speed; move stick gently all the way to the left...) compared to accurate competition methods (speed; check; stick immediately left; hold; immediately right; check...)*. Plus I've always enjoyed roller coasters
It also helps to remind me that flying is, and is supposed to be fun - its not just rules & regs and concentration and money grabbing. I know aeros aren't everyone's idea of fun, but you are allowed to enjoy doing them!
PS - definitely an advantage to be doing your PPL in an aerobatic capable aeroplane!
*These are representative - not showing actual manoeuvres!