There are lots of huge generalisations on this topic.
Everyone and every situation is up to the couple getting married. If your wife is sincere to you she will fight your corner. My wife told her parents we would not be having a village wedding. She said to them simply, would you like a party to show off or would you rather we used the money to build a house and be near the family? They accepted her views.
We got married legally at the district office, no party, no big deal and no sinsod.
Since then, as suggested at the time, we have taken care of a few financial difficulties that Mum and Dad have had but only those beyond their control. My wife has been asked and refused to pay back gambling debts or loan shark payments but has been happy to help through some other sticky situations. This in turn has helped to show Mum and Dad the value of money and how to control spending and bad habit.
In return, I have become a part of the family. I have integrated with their culture, not ridiculed their beliefs or superstitions, have accepted that they are not that well educated, turned a blind eye to problems beyond my control and, I believe from what they have told me, become part of the family in their eyes. Just their daughter's husband. Not the farang married to their daughter.
Respect is earned. Not given. A flat, arrogant, self self refusal to give sinsod is not the way to go and will be remembered. Talking about how you plan to take care of your new wife and possibly Mum and Dad a few times along the way will also be remembered, but for different reasons.