Bitcoin markets in MtGox in USD and EUR are closely connected.

Yesterday I mentioned in a post in Google+ that in MtGox the Bitcoin market in USD and EUR are closely related.
It looks like that all USD orders occur also in the EUR market.
But the inverse is not the case.
This means that the players in the USD market benefit from movements in the EUR market, but no the other way around.
Seems a bit unfair to me.
In the screenshot I highlighted the bids but the same can be done for the ask's. Left USD, right EUR.

https://lh5.googleusercontent.com/-TzebHsWBYHI/Un84c3b29WI/AAAAAAAABPQ/RIJ34EcWRkg/w1251-h738-no/Screen+Shot+2013-11-10+at+07.56.22-Annotated.png

Update 2013-11-10 (a few hours later):
I have to add some nuances. The screenshot above was at a point in time when the market was rapidly changing. At this moment it has cooled down and not all USD orders occur in the EUR order list. But the most important ones do.