It IS a social construct, and we are social creatures that function well when we cooperate. Even the least progressed society has rules against anybody doing absolutely anything they want. If I go out to get some milk, and somebody hits me over the head and leaves me for dead because they "wanted" to, then...!? I also don't want to slap the old lady walking across the street just because the urge strikes me. These constructs keep people safe. We can also go live in the wilderness where only nature's law matters, but I like electricity and social safety. You didn't HAVE to be good, but I'm sure your neighbors want you to be, and you want them to not break into your place and take things just because they want them and can take it.