This is very true.I also know that in strong families, the dharma to family will override personal beliefs. This is true in my friend Aup's case, although I still don't see him as a hard atheist at all.
The high importance placed on Dharma to one's family is often a core belief structure in Hindu families. Even my own rather liberal mixed interfaith one has a strong sense of familial obligation.
It's partly why I am rather more....."forgiving" of the Abrahamics, specifically Christians. If a Christian/Catholic Aunty asked me to attend a Church thingy and it clearly meant something important to them, then I would. Such is my duty.