Light pencil markings on the blank backs of postcard size items

[abothebear]

Maybe I'm wrong about this, but it seems to me to be somewhat common to find light pencil markings on the back of larger (postcard-size) items. Sometimes they are the workings of postcard dealers, giving details about the item and the price. But often they are little marks about the player, what team he played for, what position he played, etc. I know that each collector has their own particular taste about these kinds of things, but what would you say the GENERAL feeling is about these marks? Generally, do people care if their otherwise sharp-looking National Chicle Pepper Martin has a "3b / of" in pencil on the back? Or if their Gold Medal Foods Firpo Marberry has "1934 Tigers $3.00" on it? I care a little bit in that I'd rather it not be there than be there. And I care a tick more than a little bit if I am collecting a set and the backs don't match. But for singles, it doesn't bother me that much. For some reason, pencil marks on a blank back aren't the same as pencil marks on a card with something printed on the back. I guess because you aren't meant to look at a blank back. But if there is printing on the back, then the idea is that someone might be interested in looking. And a pencil mark there seems like a defacement, whereas on a blank back, it is bonus material.