It often is simply a lack of knowledge. Many people do not really know enough about the technology to assess the potential risks properly. Probably it also is a lack of imagination about what can be done with the data (e. g. investigate the correlation of the habit of buying unhealthy snacks and sick leaves).
In my workplace the cards for the ID system were switched to NFC. The employees were told that the range is very small and they experience that the card does not work when it is in their wallet. However they do not understand that a stronger transmitter and a better antenna in the reader may extend the range dramatically (up to several feet). There is no use telling them as they do not believe it.