Why on earth have referees started penalising encroachments on penalties

In recent weeks there have been various penalty retakes rewarded because of player encroachments. 2 examples of this are Frank Lampard's 3 attempts at West ham, and then this evenings retake for Kuyt at Liverpool.

As a referee I do not understand the grey area, so what chance do other members of the general public have. No wonder every weekend referees are abused because of the lack of consistency; the rules leave too much to scepticism.

In my opinion it should be simple; there are two scenarios when a penalty should not be retaken, despite encroachment; the first being when the penalty does not hit the target and the ball goes out of play, with the second instance being when the ball immediately hits the back of the net. I say this because neither of these circumstances would effect the outcome.

The only time that encroachment should be penalised is when the penalty is saved and the ball is gifted to an offending encroacher. The penalty should then be retaken and the encroacher should be punished with a caution for unsporting behaviour.

I would even go as far to say that the penalty should only be retaken if the encroachment is made by a defender, and a member of the attacking team encroaches it should be punished by issuing an indirect free kick to the defending team.