Low light performance is important for a lot of street photography. Being able to meter down to EV 1 @ ISO 100 is often a necessity. A very dark bar or cafe might be EV 0. Some manual meters and the Leica M6/M7 are able to meter down to EV -2 which is just about the limit of "available darkness."
Bessa R2/3A: EV1 @ ISO 100 @ f/1.4
Bessa R2/R/T: EV1 @ ISO 100 @ f/1.4
Leica M6/M7: EV-2 @ ISO100 @ f/1
Hexar RF: EV1 @ ISO100 @ f/2
Leica CL: EV3 @ ISO 100
Minolta CLE: EV 3 @ ISO100 f/2
Canon EOS 3: EV 0 @ ISO 100 @ f/1.4
Canon EOS10D/20D: EV 1 @ ISO 100 @ f/1.4
Nikon F2 with DP-12AS: EV -2 @ ISO 100
Hasselblad 203FE: EV 0 @ ISO 100 @ f/2.8
Hasselblad 205FCC: EV 1 @ ISO 100 @ f/2.8
Now EV 1 @ ISO 100 sounds pretty low (it's 1 second @ f/1), but using ISO3200 film (which is what you'd use in a really dark place), it's 1/30th second @ f/1.4. Many of us with f/1.4 lenses, rangefinders, steady hands, or monopods/tripods can shoot lower than this. Also, with TTL metering, the EV numbers are reduced by the aperture of the attached lens. So a camera meter is rated at EV 0 @ ISO 100 with an f/1.4 prime lens is only EV4 @ ISO 100 with a f/5.6 zoom. The Leica M7 with an EV-2 @ f/1 is only an EV-1 @ f/1.4, still excellent but not as stunning.
Note that this is metering and not auto-focusing. Many autofocus systems will fail at EV 2 or lower especially with dark lenses such as most consumer zoon lenses. Also, film suffers from reciprocity failure and thus the metering may not be accurate at low-light levels with long shutter speeds.