Let's take spanking for example. An ABC poll asked parents whether they spanked their children. The results varied by region and educational attainment of the parents. From the article:
"One other difference in spanking is among education groups. Among parents with college degrees, just 38 percent spank their kids; among less-educated parents, it's 55 percent."
So only 38% of parents with a college degree think that it is appropriate to use force on a child in order to get that child to act a certain way. That means that 62%, a strong majority, think that using force on a child to influence that child's behavior is wrong. If that many people truly think that force should not be used to influence the behavior of children why do we have so many laws that use force to influence the behavior of adults?
I can think of two reasons. The first is that the people who do not spank their kids are ignorant of the fact that laws require the threat and ultimately the use of force if they are to be obeyed. People do not break laws because if they do they know that the government can take away their freedom by force. Maybe some people do not understand how the government ensures that laws are obeyed and so they mistakenly favor force when the do not really mean to.
The other possible reason is that people are hypocrites. They are not against the use of force in principle, rather they are only against it when it doesn't serve their interests. Not spanking kids is the "enlightened" thing to do; parents who spank children are 20th century monsters. Similarly, forcing people to buy contraceptives that they do not want to, or to wear seat-belts, or to forbid them from owning guns or doing drugs, are all "enlightened" things to do and so in those cases using force is justified. The ends can justify the means.
I hope that the reason we have so many laws is due to ignorance rather than hypocrisy. People can be taught to see that using force to get what they want is primitive behavior. Dealing with hypocrites who want to justify force when it suits their needs and denounce it when it doesn't is a much trickier task. Unfortunately I think we have more hypocrites in this world than ignorant people.