If you get to know the lifeguards, most of them prefer the latter. I distinctly remember taking 2 umbrellas, one in each hand, and after climbing up onto the guardshack, taking a running leap into the pool.
Needless to say I had to buy 2 umbrellas least my boss found out.
I always likes horsing around with the kids, when we developed a relationship such that they listened to the rules, which really wasn't asking a lot. Don't run, don't dunk people, get out when I ask you do (adult swim, thunder/lighting) and stay out of the deep end if you haven't passed the swim test.
There are boring guards, just like there are boring people. I have found that men and women (mostly teenagers at that point) who elect to hang out in their bathing suits (read: basically underwear) 40 hours a week are usually a lot of fun to be around. There is a specific sense of self-confidence that I never really thought about until replying to your comment.
Other life guards dive into the deep end from the exhaust hatch in the ceiling after the pool is closed to the public.
I'm thankful for both types but I slightly favor the latter.