They can also go too far in the other direction...
Cow-orker in other department always leaves their ${company internal IM client} status as "Away" because they are 'tired of those marketing ppl always bugging them'. This, of course, misleads everyone else in the company, not knowing if they are even working that day.
Sometimes they change it to "Away - Here, but working" which I guess deters only the ppl that look at the colored dot, not the text. This is exactly what the DND (different color) is for, but they cannot seem to comprehend that either, even after an explanation.
Like many things...it is a powerful tool that produces catastrophic results when wielded by those who do not understand how it works.