Why?
I think this is about the only country that still uses °F - it's time these people followed the rest of the world!
Wikipedia said:Fahrenheit (symbol °F) is a temperature scale based on one proposed in 1724 by the German physicist Daniel Gabriel Fahrenheit (1686–1736)
It's all just a relative form of measurement with its own set of rules and significance, as much as its counterpart.
I also find it funny how people equally knock the use of imperial units or the English units of measure when in fact they possess some very interesting correlations with not only our fellow neighborly solar satellites, but also equally reflect a correspondence with our measurement of time as well.
Here's a link if anyone's interested: http://www.ancient-world-mysteries.com/units-of-measure.html
And a summary:
With the level of discrepancy between the British Imperial units of measure and the ‘ideally generated’ numerical values of the earth-moon system being practically none existent, no other conclusion is possible. Whoever thus established the Imperial units was quite simply a genius, for through this system one is able to naturally – in a true physical sense – combine units of time (which is a frequency) and units of apparent spatial extension.
Imperial units of measure as a whole are thus not merely arbitrary units of distance, but units that are tied in to a real natural physical cycle: that of the earth orbit about the sun itself.