I'm sure it's not really true in essence, when you make comparisons. but I suppose what really bothers private sector employees is the worry that their jobs may terminate more quickly than the public sector.
Governments may be slower to oust public employees, simply because governments move more slowly than the private sector. The public sector is after all funded by the private and not the other way round.
This means therefore that jobs in the private sector are more vulnerable - can go easily and swiftly at any time.
The private employee whose contract is based on the competitiveness of the market place, feels this vulnerablity all the time and feels annoyed, perhaps and sad that they carry this burden a bit more than the public employee.
That's it for me. Thanks for the question.