How should I handle resentment that's brewing over comp time?

Almost all our staff is exempt, and almost everyone is great about making sure the work gets done no matter how many hours it takes. We have an informal tradition of granting comp time when people have been really busting it to finish a big project. Most our employees are happy with taking a three-day weekend here or cutting out early there. However, two employees have recently taken a very rigid attitude. If they are in on weekends or working late, they want those hours comped on a one-to-one basis. That’s obviously not going to happen, so they’ve been grumbling and crabbing about it. Everyone is sick of the whining. What can I tell them to make them understand their expectations are out of line?—Joshua, Md.

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