Crank, you simply don't understand the difference between a staff ticket and a publicly available ticket. Staff tickets are generally "sub load" which means that you get a seat only if there is no ordinary fare paying passenger who wants it. That applies on multi sector flights as well. There is thus considerable risk that your holiday plans may not end up being what you signed up for.
I've been offloaded in Karachi and spent several days there waiting for an onward flight to London that had an empty seat. Also the last four or five days of a holiday can be hell as you keep having to ring to see what the loadings are, and furthermore in my day at least being stuck in a foriegn port waiting for a flight home was NOT sufficient excuse for being absent from work.
If you want final proof, the ATO looked at staff tickets to see if they came under the fringe benefits tax umbrella and concluded it wasnt worth it.
Having said that, I had a great time in Karachi (Thank you Lufthansa!).