It isn't just a proof-of-condition, but also a verification of what saddle you're selling. Given that masherz/bikemania (are they the same company?) sell a TRK for $80, someone might want to verify that that is the same saddle you're selling or whether you're selling a different SMP model.

Picture against the floor, or, heck, even concrete. No one will learn anything about you except maybe that you don't live in a very, very rural area.