Of all our acquaintances and friends we don't know a single case where this would apply, that the parents are sponging off of their kids.  Not saying it never happens but for the most part in our experience the parents are the ones stuck with helping the kids when they can financially with mortgages, down payments,  huge phone bills,  what have you,  and are often stuck picking up the pieces of broken marriages and dogs cats and children who need babysitters while lives are being sorted out.  But that's what parents are for so we don't mind and you never hear anybody complaining about it.