I have two dSLR bodies - each with a top-grade Canon “L” lens on it, one the 24-70mm f/2.8 USM, the other the 70-200mm f/2.8 IS USM. But I also have a backup small digicam - Canon’s G15 - and find it very useful, especially for some situations.
The G15 comes with a 28-140mm (equiv.) lens - a fast one at that, f/1.8-2.8. That - combined with the first of Canon’s semipro G-series digicams to really produce publication-grade photos at a very-high ISO setting - makes this camera very useful for situations where unobtrusiveness is essential, as well as for having a semipro camera that you can have with you at any time, even when your dSLR is in the car while you shop or eat. A dSLR-like mode dial - and a setting dial - allows easy setting of shutter speeds or aperture for shutter-priority and aperture-priority modes; top shutter speeds approach dSLR level.
No-flash photography is easy at ISO 3200. It’s large enough to firmly grip - and designed for firm grippability - while still far smaller than the rangefinder 35mm cameras long favored by street photographers and famously used while covering the Vietnam War by top photojournalists. It also has a very-easy-to-use exposure-compensation dial. It’s great for the same situations those 35mm rangefinder cameras were favored for - only far more versatile with that fast zoom lens.
I keep mine attached to quick-disconnects for use with a neck strap kept in the car - and on ISO 3200. And it proved handy for a no-flash, unobtrusive photo (below) of some Duck Dynasty merchandise in a retail place at the height of Duck Dynasty’s marriage-equality controversy - and that photo sold.

Shot no-flash in a retail environment with a Canon G15 at ISO 3200.
Sold through reseller to unknown buyer.