The article you cite has all the answers to this question in it. How can you say it "makes no sense"?
Quotes from your own link:
"The disaster in Japan could slow shipments of popular cars like Toyota's Prius to auto lots."
That represents supply.
"Dealers are acting on the possibility that disruptions in car deliveries from Japan will cause a shortage of higher-demand vehicles.'
That represents demand in a time with high fuel prices.
"Many smaller cars and hybrids are built in Japan, where car manufacturing has mostly stopped in the aftermath of the earthquake, tsunami and nuclear crisis."
What part of this are you not getting? The Japanese have had to close down their production plants in Japan due to a lack of reliable electricity. In full production, they produce about 14,000 cars per day in Japan. They have been down for seven days now and still are not running going into day eight. Then there are all the cars, trucks etc. that were destroyed in the Tsunami to replace Add into the mix that they still haven't gotten the nuclear reactor disaster under control which has the potential to severely restrict their ability to export anything if other countries quarantine them for increased radiation levels on their products.
If you intend to buy a Japanese vehicle, the time is now.
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