i got a arduino nano from a hackerbox, and i was puzzled by the antistaitic bag it was in. is it really static sensitive?
Electronic components do tend to be susceptible to static charges.
But ask yourself if you would rather they took precautions to get it to you in a known working condition or risk sending you one without those precautions.
so if i take it out w/o anti static band it'll be fine?
Once you open the bag it is up to you to take appropriate action with electronic components.
Completed circuits tend to be a bit more forgiving but in winter here the static build up can be pretty wicked.
There are thousands of sites that will give you advice on handling items in that regard so I wont say do or dont in any way.
If I know something is especially prone I do the band.
If it is medium risk then I touch something eg water pipe or other grounded object to mitigate the risk.