As for the party... Is it bad form, maybe. Do I care, no. Then again, perhaps we should all just trade in our houses and pantries for tents and MREs while the troops are away, or maybe ditch the houses altogether in a show of solidarity for the people effected by the Tsunami. Or not.
As far as localities having to foot the bill for security during large political events, I see that as a separate issue. And on that issue, I absolutely think the people responsible for the events should be responsible for the city services costs they incur.