The things that scare me about throw-away ticketing are:
- Short checking bags. If you are HLO that's not a problem, but trying to convince agents with a good story at the point of check-in that you want to short check has got to be a challenge. I know some people here are saying, "so, fly HLO - not rocket science," but unfortunately I'm not often in a position to do that as such. (Which would rule me out of this kind of cheat routing).
- As someone mentioned, you can only do this on one way tickets; try to do this with still sectors on your ticket and you will forfeit the rest (as per convention on most airlines). Saying that, seems that LM will allow you to book one ways as 0.5 x return so there is little consequential cost in this regard.
- Why can't LM simply deduct the extra miles from your account afterwards in order to account for the then proper ticket that you did fly? Saying that, I suppose there are no provisions in the rules for them to do so (but programs always reserve a "get out of jail free" clause for them to do what they like); your reason for throwing away the last sector needn't be true per se. Then again, people regularly buy cash one-way tickets or return tickets and throw away the very last sector, and apart from a few isolated interesting incidents, I haven't heard of anyone being sent a bill for the difference resulting from the real flown sectors.
- If you make a habit of throwaway ticketing, the airline might get onto you..... which again might mean nothing...
I think when BD DC was in full swing, people used to route to KTM for similar reasoning w.r.t. zones etc. (or either that or the availability seemed to open up somewhat). Either way, I think I remember hearing that BD got wind of the idea, and started telling their ICC staff basically to stop routing people with obviously silly routes to KTM and enforce more direct routing, and further to that also increasing the routing restrictions on redemptions (i.e. insisting on particular routing surcharges).