That's exactly what a limiter does - it makes the sound louder and punchier, by bringing up the average level. Don't confuse dynamics with being just louder - it's also about reducing those peaks (that don't contribute to the sound) in order to increase the overall level.
If a single snare hit 1/2 way thru the song is louder than everything else, the mastering engineer can pull down that one hit and increase the level of the song by that amount without touching the other dynamic elements of the music.