She probably knows, unless all of them are the same model, another thing is she understands or bears with it. Yep, usually, a point is reached where is not that much and if she can also afford her cravings then happy wife, happy life.
Sometimes I'll loosely throw something out to my wife like I want a new car or another watch and she will unexpectedly say, "okay". I'm surprised to no end and I'll start looking and getting serious and it will hit me, we can't really afford it right now and I really don't need or want it. LOL