Hard physical work does damage your joints over a long period of time. I have bad knees, from a fall many years ago, from a job where I stood and walked 8 hours a day for nearly 30 years, and from being overweight.
I agree with bsmart -- I have lost weight and I've had the shots. First I had the cortisone shots, which I wouldn't recommend to anyone because of the side effects. Then I had the hyalgan shots -- that's the rooster comb stuff -- and it helps. It took three shots and some time but eventually it helped. It's 30 seconds of misery and about six months or more of relief, definitely worth doing.
I couldn't exercise much before the shots, but now I'm up to 30 to 45 minutes of walking at a time without my cane! I think I probably can manage without surgery if I keep losing weight, walking and getting the shots as needed. I'm so thrilled about it, too -- last year I could barely walk at all, this year I can walk much more.