..or use high ISO. When you take pictures in a restaurant with dark high ceilings and walls – nothing much to bounce off – you get bad pictures – the flash pictures love to hate.

Even when you use a Gary Fong Lightsphere:

Better, but clearly not panacea, then: this light is not ideal. Harsh shadows, flat light, unflattering skin.

So under those circumstances, it is OK to use very high ISO. 1600 ISO at f/4 at 1/60th second, with a bit of bounce (even high, far walls and ceilings will bounce something back), gives me this:

Better, and perfectly OK for large prints, and it avoids that clearly “flashy” look.

You can also use a slow shutter speed (on Nikon cameras, engage “Slow Flash”; on Canon cameras this is normal in Av mode).