How old are you? Is your finish as good as new all over?
Its not unusual to find a gun over 80 years old to have some minor imperfections in the finish. We can guess that its some dulling due to how it laid in a box, closet, or desk drawer for 60 years. Its also nothing to get very upset over. How old is your car? Does it still look the same on all surfaces? When a part of your car starts to look a little dull, you give it a good wash and then wax it. The same treatment often works to some extent on a nice old gun. There are some wax products you can try to polish out the "bad" area. Wax works just as good as most oil for preserving the surface and denying air and moisture the ability to interact with the metal. A good cleaning, very little wax and a very soft cloth, like a towel or diaper. Whoops, they don't make those anymore, do they?
Don't get upset with the gun until you've tried everything. You're just starting on the gun. You paid shooter price and its probably going to be a very good one. Chances are if you spend some time, it'll look nearly new again. You need to worry about ammo.