Most people retiring aren't as fortunate as your Grandparents. The effect of the baby boomers will be a reduction in income tax revenues because they will no longer be working and increased government costs because of higher social security payouts. Its also expected that they will live alot longer than previous generations and will cost more in health care. The same type of problem will be happening in the UK too. Its a good time to be in the business of supplying goods for peeps aged 70+
Honestly, I don't know how they spend the money they do. Not rich, but they've lived a full life. Don't forget medicare. Medicare will break the back of government or it will be reduced to nearly nothing. Everyone, actually. Japan and China will be raped by their demographics. Tons of old people. Japan especially, since they immigrate no one. They'll own the market, and the congress for quite sometime. That's why both sides of the congress are afraid to touch SS or medicare (seriously), because it's politically unpopular. Europe, Canada, America, Japan... will all have to chose between incredibly high taxes or huge limitations on their entitlement programs. Liberal programs will be marginalized by impratical demands. It will happen, no matter what. As-is, is impossible.
Chinese people have tradition of saving to prevent future possible expend such as disease,educations etc.