[update] If you are happy with an older version (Drush 5.10) then you could install from Debian repos.
sudo apt-get update && sudo apt-get install drush
Note that git is a suggested package but it shouldn't auto install by default. Reference: https://packages.debian.org/jessie/drush
If Drush 5 is too old then you can always re-evaluate your options then...
What version control do you use for your server/CMS/etc? If you don't use version control then I would strongly argue that you should just learn how to use git. IMO it is the most awesome vc system that I have ever used... I would say that using git (let alone installing it) is pretty common dev practice!
Regardless there are possibly ways to install drush without installing git but you could just install git then remove it again after if you don't want it!? AFAIK drush now requires composer to complete the installation and I'm pretty sure that needs git too. So perhaps just bite the bullet...
So my suspicion is that even if it's possible then it will be a lot more painful and a lot more mucking around...
For the record this is how I install drush (latest dev version) then use it to install drupal8:
# install composer
curl -sS https://getcomposer.org/installer | php
mv composer.phar /usr/local/bin/composer
# install drush dev-master
git clone --depth 1 https://github.com/drush-ops/drush.git $SRC/drush
ln -s $SRC/drush/drush /usr/local/bin/drush
ln -s $SRC/drush/drush.complete.sh /etc/bash_completion.d/drush
mkdir -p /etc/drush
cat > /etc/drush/drushrc.php << EOF
// by default use the drupal root directory
\$options['r'] = '$WEBROOT';
# download latest drupal8 and install
drush dl drupal-8 --destination=$(dirname $WEBROOT)
mv $(dirname $WEBROOT)/drupal-8* $WEBROOT