Because the current owner has played it a bit more in the last 15 years, perhaps.
Knowing as little as I do about vintage Fenders and finding the whole thing about refinishing a bass knocking enormous amounts off its value ludicrous, I would suggest that the checking showing up in the finish is the reason that it was "restored" rather than "refinished", so the majority of that checked finish could be kept and just the enormous graze on it be cleaned up a bit - scrub the wound out, slap a bit of emulsion on it, that'll sort it.