PCLZIP_ERR_BAD_FORMAT from WP CLI or WGET

[eriktdesign]

When using WP-CLI or wget to download a theme from underscores.me like this:
wp theme install http://underscores.me/?underscoresme_generate=1&underscoresme_name=SITENAME
or
wget -O kansasfpc.zip http://underscores.me/?underscoresme_generate=1&underscoresme_name=SITENAME

It doesn't work. I get the following error message:
Warning: The package could not be installed. PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature

Any thoughts? I was hoping to really automate my jumping-off process, but this is a bit of a hurdle.