It is a Tsunami

We have a small discussion in language class about an article post in newspaper. The writer argued that using Tsunami to refer to the current financial crisis is incorrect. To him(or her), Tsunami is the natural disaster that due to earthquake at seabed, which sent giant waves to the shore, and claim thousands of life. In the financial crisis, he or she don't see people losing their life, they just lose money, so, he reject the usage of the phrase ' Tsunami'.
That is the basic idea of his article.
However, we all agree that Tsunami is a perfect word in describing the current crisis in market. The language scheme that the original writer use is called Metaphor, and he or she should be credited for selecting the correct phrase. It is refer to the major disaster that is facing by people around the world, the turmoil in market. And although no one will lose his life(of course), but it bring suffer and pain to everyone.
And besides, if the Tsunami occur in a place of no people or life, no one will lose their life for sure, then is it, a Tsunami?
The usage of language schemes is to add rhetorical effect in a passage, to catch the attention of the readers, and make reading more interesting. And metaphor has always been a common schemes that writer used, as to compare a situation with another phenomenon more lively. So, why should be so rigid in language and be robbed of the fun in reading a literature piece?