Can any ol' employee tell you to leave, or can you insist that the manager/owner do it? Like, if I'm grocery shopping, can a stocker or bagboy tell me to leave, or does the manager on-duty have that power?
Legally, anyone who works there can tell you to leave or disarm and you can either leave, disarm, or face a trespassing charge.
C.R.S. 18-12-214-5
(5) Nothing in this part 2 shall be construed to limit, restrict, or prohibit in any manner the existing rights of a private property owner, private tenant, private employer, or private business entity.
Part of what makes Colorado's gun laws better than other states, in my opinion, is that they are vague and the interpretation is generally taken widely instead of narrowly. What this means for the statute above is that because the line does not exclude employees in the business who are not managers, owners, etc, then the rights of the employee to enforce a no gun policy within the business are valid under existing property rights laws.