You are conflating the ‘laws of statistics’ with other issues of sampling, polling methodologies and market research problems in general.
My experience of consumer research (over forty years) tells me that people are complicated.
In research terms, what that means is:
- they don’t really know what they think
- they often don’t say what they really think
- they don’t always do what they say they will.
What this means for the quality of your data, go figure …