netcat does not works in heredoc style -

i trying make request 1 of apache based web server using netcat. surprisingly following 2 formats work expected. style suggested on netcat manpage:

$printf "get / http/1.0\r\n\r\n" | nc 104.131.x.x 80

and

$echo -e "get / http/1.0\r\n\r\n" | nc 104.131.x.x 80

but, below 2 style such heredoc convention or line line command not work , responds 400 bad request.

$nc 104.131.x.x 80 <<eof > / http/1.0 >  >  > eof

and

$nc 104.131.x.x 80 / http/1.0\r\n\r\n

any idea, why similar header information acts differently?

RT