comp hours versus bonus plan

[Guest waynev]

Currently I work as a manager for a company that has ten different facility sites within the state. Managers at each site are given responsibility to find substitution of staff when they are absent (vacation,sick,etc.)from work. All staff are paid salary. Each facility is unique in the services they provide and the contractor they work with. One manager simply requires their employees to work extra hours since they are salary. Another manager offers comp time. Another manager hires substitutes or independent contractors for the day(s). Another manager arranges for bonuses to be paid according to the hours worked. I have been told offering so many different plans is illegal because they are not equal within the company! Each plan works within each facility but no plan covers the needs of all facilities. What is legal?