Why would you use the libtorrent client?

[zabadoh]

I'm seeing a lot of "libtorrent 0.3.16" clients in one of my torrents.

I understand that libtorrent comes with a simple command line client, is that what I'm seeing these peers using?

Why am I seeing so many of them?

[jjbot]

Most probably those are rTorrent clients often used on seed boxes.