Order has nothing to do with it. In fact, the amount of information (order) you can pack into a communication channel goes
down as the band gets narrower; why do you think internet communication companies tout their
broadband service? What do you think that word means?
The reason people use narrowband radio signals to communicate with each other is because it makes it easier to distinguish from natural radio sources (which happen to be broadband, and which do contain quite a bit of information, actually), so less power is needed. Since aliens will be subject to the same laws of physics as we, it stands to reason that they will use the same technique.
That does not eliminate your problem. If "INTELLIGENT" life exists, it is capable of ordered communication, otherewise, it would not be intelligent. Whether that communication be from broad or narrow bands makes no difference. Intelligence implies order. Period.
The reason people use narrowband radio signals to communicate with each other is because it makes it easier to distinguish from natural radio sources (which happen to be broadband, and which do contain quite a bit of information, actually), so less power is needed. I can understand your statement - because it is ordered, and from an intelligent source - you. I conclude that there is an intelligent life form (you) that sent me this message. That is my only logical conclusion since non-intelligence cannot communicate. (smile)