To make this argument, we should first point out that employees are in a public place when they are working. Therefore, there is no reason for them to have an expectation of privacy. This is even more true given that the employee’s surroundings are the property of the employer.
We should also point out that employers have strong interests in intruding upon the privacy of their employees. Businesses need to be sure, for example, that employees are not using firm-owned computers for private purposes as this would waste the employer’s time and money. Businesses also need to be able to do things like drug testing their employees to ensure that they will not do substandard work and/or endanger others.
With the exception of personal body privacy issues, then, we can certainly argue that employees should not expect to have any part of their work environment remain private.