Earlier quoted context omitted.
Familiarity and low resources needed .. I can use a $5/year natted VPS and program (via Git/Vim), run scripts, surf the web (links), chat on IRC (Weechat) and continue my Tmux/Screen workflow on basically any *nix machine with at least ~16MB memory.
why do you need to use low resources?
Easier to access / run things on remote systems.
Possible to create tools for use on small systems -- your DSL/Cable modem, say, which is really Just Another Linux Box, though with tiny capacity.
Smaller VMs -- less system load, more available, greater flexibility.
Run a shell on your Android or iOS device. Full power of the shell, scripting, and development tools.
You can do more of whatever it is you want, faster, using less. It's an efficiency thing.