Surely the real question is why has it taken so long to check shoes? The easiest way to take a Stanley knife blade through security is within the shoe. Whether it should be just pilots or everyone who should be checked is debatable.
The reality is that infiltrating a terrorist into the crew of an aircraft is the easiest way to achieve their ends, especially using cabin staff.
What we really need is proper profiling of staff and passengers, until that happens we are all very vunerable.