I find that interesting, and also concerning.. but I suppose it depends on the office culture.
I tried to ignore my peers and direct reports salaries when I first moved into management... I lost an employee after 2 years when another place offered him a 80% raise.
At that point, I realized I couldn't count on a 3rd party to properly evaluate an employee's worth, and I started to take an active role in ensuring people are paid as close to market as we could afford (though, as a non-profit, we struggle to compete for technical talent)