I am on salary here and I carry a pager/cell/laptop for work when I'm on call 2 weeks as "primary" and 2 weeks as "backup" every 10 weeks (5 people in my group, we rotate.)
Primary typically gets about 5 to 20+ pages during their 2 weeks. They typically get 1 "comp day" for the 2 week primary rotation. It's perfectly legal.
If you don't like the policy then talk to the management about how you think it needs to be changed to be fair, if you are unable to reach a compromise, then it's time for you to look elsewhere for your employment.