Bank of Mum and Dad

Why is it that some adult children cannot manage financially and still rely on Mum and Dad to bail them out? A lovely couple we know have 3 children in their forties all working, married with their own children and their own homes. Admittedly they probably have big mortgages but do not appear to budget according to their needs. They don't go to Mum and Dad for help when their car breaks down, the boiler is not working or they are unable to feed their children. It is to fund a luxury lifestyle that they feel entitled to expensive holidays, designer clothes and the latest gadgets. Perhaps they should think more about their parents and their needs in their older years rather than putting themselves first. What do you think?