If you are a leader, the people you are charged with leading need you to take your time off. During the week, you have tremendous influence over their priorities and agendas. Often, they put your requirements first - working for you before they even address their own needs. And, there is nothing abnormal about this; the organization has entrusted you with the responsibility to perform this function.
Simply, recognize the magnitude of your impact and take your time off. During your time away, employees utilize your down time to innovate through working at their own pace and via their own processes. Further, your time away affords them time to attend to mandatory but personal administrative matters. For example, my organization requires us to complete 40 continuing education credits a year, and I rely on my team lead's off days to complete these requirements.
When you work around the clock, refuse to take your vacation time, and work through your scheduled days off, you are denying your employees a chance to have a break from your agenda and priorities. Further, you are establishing an environment where, while taking vacation time may not be frowned upon, it seems like it is because you are never away demonstrating that vacation time is a must for maintaining the health of the individual and ultimately that of the organization.