It's A Bad, Bad, Bad, Bad World (1) - S6-E22
Other mistake: Isn't it amazing that both evil Paige and good Paige have the same exact rocks on their "sides" when they're fighting in the underworld?
It's A Bad, Bad, Bad, Bad World (1) - S6-E22
Other mistake: Phoebe says there's nowhere to park except blocking the neighbor's driveway. We can see in the opening shot that there is no-one parked in front of the manor, and we see spots across the street. There is also enough room to park where she is without blocking the driveway. At the end of the episode, despite not moving it and also saying that she hasn't, it's not blocking the driveway any more. The patrol guy still shoots her. It's not illegal to park there unless it's blocking the driveway.
Answer: That was a mistake in the series.
Also, the episode is called 'Babies First Demon' and this alone tells us that it's Wyatt's first time in the field (so to speak) and as the sisters say, they've done a good job of clearing up their own magical messes so far. Nobody really knows how advanced Wyatt's powers are, or will become. That's why the cleaners appear, to nip things in the bud. The Cleaners didn't want to chance that the sisters could clean Wyatt's magic up, just incase they couldn't. Therefore intervening themselves, just in case.