Yeah, I do not think most haggle because they cannot afford the full price or for care, they just want a better deal. If someone puts prices firm in the ad or it is a especially rare or fine example, I will not haggle.
Otherwise, I assume there is room to negotiate, and there usually is.
I even see a lot of ads nowadays that even say "negotiable" or "OBRO."
With that said, if I do pay less than advertised or less than market, I keep that to myself.