Everyone wants to be paid more than they are of course and I'm no exception, but overall I feel like I am being paid pretty close to what I am worth. After accounting for the fact that I work for company with a decent culture, don't take part in an on-call rotation and pretty much get to pick my hours outside of scheduled meetings. I know what the market rate is in my area for my skills and experience, and I negotiate my pay (and raises) with my employer according to that data.
What _would_ hurt me (or at least my image) is if someone who does similar work to me went to their manager and said, "hey manager, bityard says he makes $x more than me, please give me a raise." Now maybe the manager is a completely reasonable guy and agrees completely. But it's a small company and maybe that particular manager isn't so reasonable. Now I'm the bad guy in that manager's eyes for "bragging" about my take-home pay and making him do the work to convince _his_ managers to approve the raise and justify the increased operating costs, passing along my name discreetly to them as well. Or maybe the raise is denied, and the guy quits. Then I'm the bad guy. Or the raise is denied and the guy is fired for something unrelated. It all gets murky and resentful real quick.
Further, if you ask someone at work what their pay is, how do you know they are telling the truth? I can think of several reasons people might lie about what they make by shifting the number in either direction.
At the end of the day, going to your boss and saying you and the other employees compared salaries is frankly a pretty lazy (and likely ineffective) way to ask for a raise. The _right_ way to ask for a raise is to do your own research on market rates, and then _prove_ to your employer why you deserve the going rate (or higher) based on your work performance and other relevant factors. As it always has been.