The difference is that when you are subject to accusations in the media you're aware of them and able to respond. We've had an individual, a member of our association, just get a letter saying “We've just closed an investigation on you that we've been conducting for seven years”. That person wasn't aware that an investigation was under way.
The problem in having multiple, simultaneous parallel investigations on the same set of facts is the potential for different conclusions. What would the courts do if the RCMP cleared somebody of placing a public office holder in a conflict of interest, the Commissioner of Lobbying found the lobbyist guilty, and the Ethics Commissioner said there was no conflict of interest in the first place?