I don't sell very often but when I do I don't ask the buyer to pay MY fee's or ask for gift.
When buying I will automatically pass on any sales thread that say's "Gift or add xx% for fee's".
Hopefully if enough do the same it will catch on but I think these threads on the subject that come up from time to time have value and are very helpful.
I think a vast majority of sellers, especially the newer ones to BFC put the fee's in their ad because that's what they see most other people doing and don't know it against PP's Terms of service.
Let's be honest, how many of us actually read the TOS when we first signed up? I know I didn't. It was a thread like this one I read some years ago that made me aware that asking for fee's or gift when purchasing good's was against the TOS.
I think most sellers want to do the right thing in the right way and threads like this help raise awareness.
The OP makes a great point also. Deals made here require a degree of trust and honesty. What impression does it give if the first thing I see is that you are willing to cheat PP out of their fee's or make a buyer pay YOUR fee's knowing it's against PP's TOS? Not a good one. Makes me wonder, Can I really trust your description that the knife you describe as NIB or LNIB, never used carried or cut anything is really in that condition?