Wedding photographers probably process most of their images before viewing/delivery. The customer is paying for that service.
Most of my business is youth sports, where 0% of the images are PP'd before client viewing. We shoot to sell, so what the sensor sees is what the customer sees.
We have some events where we sell after taking photos: if they buy prints, we'll touch (crop, possibly color correct and NR) every one of those before printing.
But about 40% of the photos are bought in digital format where they get what the camera got, burned straight to disc and delivered.
Other events, we burn everything straight to disc: 350,000 pix in 3 days went home with 12,000 competitors and coaches from 50 different countries at our last major event.... all straight from the camera.
I do studio photography of high-end hand-made musical instruments. 100% of the photos the client sees are post processed. No one gets to see the "straight out of the camera" shots unless they attend the shoot (which I discourage), and no one gets "all the shots." For a typical shoot where I need to deliver 5-7 finished shots, I'll typically shoot 60-100 shots across 7-10 setups.
I don't shoot for clients but every photo gets post processing in the form of capture sharpening and noise reduction suitable for the ISO and camera. Then I zap the obvious crap, and then I review and tweak some more with white balance, cropping, better sharpening, exposure, contrast, highlight and shadow recovery, etc.. Then I rate and keyword. Later on I'll get around to serious pp to suit large printing or whatever.
