Honestly, my favorite day to actually watch the golfers is the Tuesday practice rounds. It's interesting to watch how they analyze holes and determine bail out areas, etc... If you're a golfer, find someone you like and follow them for a couple holes. They will roll balls all over the greens trying to guess at the various hole locations and generally go all around the greens to try and figure out bail outs or where a misplaced shot might land. It's fun to watch them drop a 2nd or 3rd ball and try different clubs, elevations, approaches. If they ever hit the same club a 2nd time, it's usually radar-locked to the target. They really are freaks.
I also like playing hookey on Fridays and being out there, but on the weekends with bigger crowds, you can't beat the view from the couch. I usually give weekend tix to clients. The PGA Championship is here in Charlotte next year at Quail Hollow and we just ordered our tickets a couple weeks ago.
Surprisingly one of the worst viewing golf experiences I ever had was the Ryder Cup at Valhalla in 2008. They let huge crowds on the course and in team play everything is congested in to 2-3 holes, so it's hard to see. We ended up staying at the corporate tent where we had free drinks and food and just watching from the deck when they were on the hole we were on. Still a great environment, but not viewer friendly at all.