I would say that parents must understand that the time of living with children is gone, so whether you are able to do less or more for your children, but make sure that you arrange for your old age, and never live with children. I have seen that wherever parents are rich or earn more than the children, they are respected and certain discipline is followed , but once children start earning more, DILs become totally irreverent and arrogant without any discipline in life. So whether we like it or not money matters.
Somewhere most of the people cant give up a life of comfort, even if it comes after forfeiting self respect, here I differ.I believe in living with dignity, may be without material comfort or some day to day problems even..Now the onus is on the older generation...what they want...to trade their dignity for comfort or live on their own ...to take the crumbs or live with self respect..
You have done you job with bringing them up, now let them live, whether they do their duty or not is their outlook...,,you must let them be free....