Depending on the tires used and how the car is driven having a bit of negative camber (top of tire angled inward) may be desirable for improved handling. It's also a natural consequence of a lowered suspension, unless the owner takes car to either add in adjustable toe links or camber plates and adjust the negative camber out. Typically cars come from the factory with 0 camber, which optimizes the tire patch in straight-ahead driving - and hence optimizes braking- and also optimizes tire wear. But a couple of degrees of negative camber can help reduce tire sidewall "roll over" in sharp cornering, improving grip in the corner abd reducing understeer, so it's a mod that autocrossers and track junkies typically employ, ecven thoigh it leads to premature wear of the tread along the inside edge. And for the really agressive driver using R compound tires for track about 3 degrees negative camber is recommended for best grip.
Of course dialing in negative camber for the aesthetics only is a fad that some will do - like "upgrading" to over-size rims and rubber band trires, or "slamming" the suspension to reduce gap in the wheel arches.
M4 convertible, F15 X5 xDrive35i
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