I think the employer sets the stage for the culture and environment for the workplace. ex. The employer is the one who can influence policies on casual dress, flexible hours, establishing pride in the company and individual accomplishments, etc. We often hear about what companies are good to work for and why.
The employer/management sets the TONE for the culture in the workplace.
Like most things in life, it depends most heavily on the realationship between different elements rather than the elements themselves
Work doesn't need culture
I don't think so because the management and owners make the rules - not the employees, however, there can be a lot of groups within any company.