shrewd marketing by Davis to get the extra bucks from an accessory
I really think people are looking at this the wrong way... I kinda of think of it as a very smart manufacturing decision.
If I were a dealer, they are doing it exactly the way I would want them to do it.
While most of us think of connecting to a computer, Davis actually makes a number of different data loggers that do different things. They all plug into the same "generic" port which kept the costs of designing the Console down.
It allows them to have more options with less cost overhead using the same console.
The three on their website now are (I've been told they have other custom ones as well):
Part#06544
Part#06510USB
Part#06510SER
If done the way that you are suggesting they do it, they would have to have at least 3 different consoles. That would greatly increase the complexity of stocking the various units and bundles they provide for both manufacturing and for their vendors as well. Basically you would have to multiply everything by 3 or simply not stock some of them.
They way they have it now, they can bundle packages with the same console and the consumer can get what they need for communication assuming they even want any communications.