Welcome to the forum. Are you concerned about the spotting on some of the leaves? Were they not there at the time you bought the plant? It appears to be the result of a liquid being sprayed onto the leaves. Leaves of some citrus trees at the stores look similar because a fertilizer and/or fungicide had been applied by the grower. Have you inspected the plant for pests? Is there any stickiness under and on the plant itself? Is there any webbing present? By the way, in case you do not know, your plant is a Ficus benjamina, Weeping Fig.
I see what you mean now that I look more closely at the photos. I used to have one of these plants and it had a substance on its leaves but not nearly to the same extent. I thought it was something natural for the plant, probably the phenolic compound described in following document: Those Finicky Ficus!!!. I wonder if what you're seeing is an accumulation of that substance that has dripped from leaves above.
