Could do it cheap wrapped like this
I remember that one!
Good arguments on both sides, though the price is pretty hefty, even with time and labour. Personally, I keep a bike box and a few smaller package items around when I've ordered stuff and then recycle them if I ship something. My post office is in walking distance, however, so no petrol issues. As for packing stuff, I don't consider it labour (me personally) if I'm selling something. Ususlly I'm happy it's been sold and consider the 10 minutes or so it takes to pack it just part of the process.
I would do, and have done, the same as Pickle. Ask if they'll use a different/cheaper posting method and if not I reconsider if it's worth it to me. If it has to do with insurance and tracking numbers, it's also for their protection so I'm okay with it. If it's to justify labour etc. I might just say fair enough but not bid. Hmmm, so how much do you want/need yet ANOTHER frame Pickle?