Staffing the minimum...

Okay this is a rant.....
I just got a call begging me to come in for a few hrs to work ("You can bring the kids") just to help out for the resident Xmas party. The reason they need help is because they are always staffing the bare minimum to meet the nursing hrs and today will receive a new admission or poss two. Why in Gods name to they have to staff so low when they had a party planed for the residents??
I'm not even sure they are having a party for the residents since all I've seen posted was for a staff party that 7-3 was planning for themselves. This makes me soooo mad, because I feel so guilty if it was for the residents, but why wait till the last minute to get help... Everyone knows that the hospitals are dumping their pts for the holidays...What probably makes me even madder is that all administ/office staff will promptly be leaving at 3 or 4pm (party was scheduled for 2:30). Ugh Happy HOlidays!