sort with tab field separator

[Amadeus W.M.]

You would think specifying tab as a field separator for sort would work 
like this:

cat file | sort -k 3 -t "\t"

It doesn't:

sort: multi-character tab `\\t'


So after a little search and some trial and error I got this to work:

cat file | sort -k 3 -t "`/bin/echo -e '\t'`"


For my own curiosity, can someone please illuminate me as to why the 
first incantation does not work as expected? Is there a more natural way 
to specify \t other than echo?