The minute you set a price you are going to get lowballers and with prices on most already set at sub-1k, the seller probably decided it isn't worth the aggravation for such small margins.

Couldn't you argue the same thing for anybody with a reasonably priced pin,whether they be a private or commercial seller?

Don't get me wrong if these were over in Perth I would be straight there having a look, however the justification for not having them list prices makes no sense to me. Private or commercial sellers, why would they be treated differently in regards to getting low ball offers? If I list a reasonably priced pin that is accurately described should I be immune from giving a firm price? I priced my pin at least less than $1,000, so that is fair by some arbitrary measurement therefore I am immune by default from listing a price WTF?