When basket countries (Greece, portugal) were added to EU, what do you expect? The rest of EU keep sending ton of money to keep them afloat. The donor countries have to cut corners somewhere. Then new countries (Estonia, Cyprus, Latvia, Lithuania, Hungary, Malta, Poland, Slovakia and Slovenia) are quite poor, so in essence they keep getting free funds. Moreover, the EU agreement stipulates no restrictions on other EU citizens moving to UK and working there, however the non-EU nations quota is only 100k. There are 1 million polish people in UK right now, which is quite high. It is so high that indian grocery stores in some areas of UK are adding a Polish section or are completely opening stores to serve Poles interests only. UK sends in total 8.5 billion GBP/year to EU than it gets back (they send 13 billion and get 4.5 billion back)
EU itself is flawed. The Northern european countries should have been part of the EU and no-one else. You cannot run EU with so many weak links (16).