Right, I still have several pairs of 501s of nearly that vintage but now I'm having difficulty fitting into them. I've never had one of those riveted buttons part company with any jeans whether Levis or others. That riveted system works very well. However, I've had several come off Levi jackets usually during rough activity when I've been caught on something and they've torn out. No problem, I just stitched up the torn area with needle and cotton leaving a hole that the riveted part passed through and replaced the button with an almost identical generic type that comes in two parts which just screw together. Problem solved.
