Glory
There is a lot of pride that comes with lifeguarding. It's like being a fireman or an EMT. While others go about their jobs selling things, you're selling safety and saving lives. How much more noble can you get than that?
You'll have the respect of your peers and elders.
Even if you're only working at a pool for the summer, brag about it on your college application. How many jobs out there pay you to be a hero and to get a tan at the same time?