[laumars]

Most people are not at uni and rented boxes usually have root open by default expecting customers to then disable root access and create a user with su / sudo rights. Plus I tend to take things further and create a dedicated groups for ssh so that rsync / sftp users cannot use a system shell nor port forward and are chrooted while a very small subset of administrators have full ssh access.

Plus even if you do borrow someone else's box, can you be sure that they'd even be grateful that you're using up their bandwidth?

Ssh is a dangerous protocol to leave open to the WAN, so setting up an ssh server properly, while not a time consuming job, will still take longer and more effort than simply deleting a few files afterwards.