muggins - perhaps I should have qualified East Europeans by saying transient E. European workers (those that come here for 3-6 months). I've known a good few East Europeans and there are some who've decided to settle here permanently/long term and contribute to the economy much the same as Brits do, thing is they are probably in the minority.
A lot of them still come to do short term work, will happily sleep several to a room (some grew-up doing this as their homes were so small), they'll use minimum heating (they grew-up where winters could get to -20c), some will even come with a month or so's supply of food, they'll pay taxes but will claim a tax rebate when they leave. This is all stuff I've either seen with my own eye or East European friends/colleagues have told me that they are doing or people they know are. So compared to someone living here permanently (of whatever nationality) they contribute less.
In my books this is all fair enough and you can't blame them if they can earn a years salary back home for 3-4 months work here. Didn't British builders do this sort of thing in the 80's and hence inspired auf wiedersehen pet?