The word is an apt description of something very real and very common [0]: people hiding their greatest moral failings behind ultimately empty virtuous performances.
It's unsurprising that the only people calling it 'loaded' and despairing over the existence of the term, identify with the group it's most often used to describe. And it's unsurprising that they would misunderstand it to be a term that you use to describe virtuous acts instead of sanctimonious frauds.
Desperately wishing that you were able to police the language of your political rivals isn't a good argument for getting rid of a phrase.
Also, if every time somebody uses the term, and somebody jumps in to say "I think you mean 'they're being a sanctimonious hypocrite'" then really it will just be emphasizing the meaning. I don't see what you expect to gain from this...
[0] http://www.thewrap.com/joss-whedon-feminist-hypocrite-infide...