While exclusives like the modulars are always available on amazon.com (sold by amazon.com, and of course as long as they are, in fact, available), the same sets are not sold by amazon.co.uk (on that site yes, but not by amazon.co.uk, only by resellers for respective prices). Does anyone know the reason for this? Is amazon.co.uk maybe simply not allowed to sell exclusives, while the same site in the US is? The same seems to be true for, for instance amazon.de. Rather disappointing.

It´s not a hard and fast rule - Amazon EU have stocked a number of exclusives in the past and they occasionally pop up in very low numbers so you have to be quick and the discounts aren´t much better than double VIP points.

There seems to be some collusion between the two companies not to offer these sets en masse, though.