How many stops do you think there are in a typical concert setting?
40? 60 ?
Every real world scene vastly exceeds the dynamic range of film or digital sensors. The trick is figuring out which real world values you want to map to the range of the sensor/film, and how much relative distance (contrast) you want between them That is the essence of the Zone system.
For example, your film or sensor may be able to capture 12 stops of range. Any object relatively brighter than six stops from the middle is a solid blown out highlight and any thing below stops from center is a solid blocked up shadow.
So you decide that the whitish flower in the hair of the singer should have detail (+6 to +4), the dress (+3) and the skin (+1 to -1) can fit in the scale too. Mic handle (-4) and the hair of the background singer (-6). The rest falls outside the range.
This is a crude example, and not meant to be a real world condition, but it illustrates the idea.
Greater DR at a given ISO is important because it allows me to pack more tonal information into a representation of a scene.