Flaw or Improvement?

This is the second story on this report I've come across today. The other was on National Public Radio.

Both treat the absence of a "sweet tooth" in cats (lions and tigers and house cats, oh my!) as a "flaw" or "dysfuntion".

Wouldn't it also make sense that such an evolution would make the cat an even more efficient carnivore, securing it a niche in the animal environment, as it eschewed anything but meat on the run? (While the dog is lapping up ice cream, the cat is pouncing on birds, mice, moles, voles and more.)