If you use metal containers you have to pick up the container to ground it to your body (or have it on an anti-static worksurface to which your wrist is attached) before placing components in it or taking them out.
If you get it wrong (forget to ground yourself or the container) they pretty much guarantee destruction of the chip as the first pin to touch the metal undergoes a sudden step-change in potential before the others can catchup, Given static charge potentials are often 100's or 1000's of volts in dry winter conditions, this is clearly bad news.
Anti-static bags and containers have very high (but finite) resistance, allowing the first pin to contact to discharge the chip slowly without a sudden big voltage discontinuity at that pin, which is more forgiving of careless handling. For a beginner I recommend the latter approach, for professional electronics assembly full anti-static precautions every time.
In relatively humid conditions you can get away with really sloppy handling as static doesn't tend to build up then 