I think it has more to do with what Boomerang 1 wrote. It's a marketing issue. Anyone who'd been around jets more than a few years knows that taking the prop off a given plane magically ups its value by double. Even a wood-kit jet is going to cost more than a prop-driven wood kit of the same or higher amount of stuff in the box.

It's similar to when you order a flower arrangement for an anniversary party at $12 per pot. That exact same arrangement in the exact same pot will cost $40 if you tell the florist that it's for a wedding. That florist knows that people will abide being 'bent over' when they're paying for wedding eccoutrements.

Smart companies use this psychology to their advantage. Often times, the higher-priced item is assumed to be the superior item. Though this is often not the case, it's a useful consumer tendency for a company willing to market products that way. Also, everyone has seen those guys walking around like a proud father because he just plunked down umpteen thousand dollars on an ARF jet (that someone else assembled). That kind of mentality doesn't go unnoticed by manufacturers. In fact, you don't have to look far to see manufacturers offering their used ARFs (whose total price of components might be 5k) for umpteen thousand dollars to try to boost the perceived value in the minds of consumers who might be potential customers down the line. That way, they can say, "Look what a good investment this is!"

At the end of the day, it's all about what a customer is willing to pay. People might be willing to spend 3k on an airframe offered by a company who pays a Chinese manufacturer to build it. That manufacturer may turn around and sell the same item out of the back door for $1500. When the customer sees that, the first company is kinda screwed because suddenly, that item is only worth $1500 in the customer's mind. I think we've seen examples of this a lot lately in this facet of the hobby.