Last year I did some work for the Greencore group & when talking to some managers I discovered that if it were not for migrant EU workers who were willing to do the repetitive jobs in their factories that many of them would have had to close. They quoted the pickle factory in Selby as a prime example, they had tried the UK born locals, they had even tried the surrounding area by providing transport to/from Selby but they could not recruit......they could not increase wages as profit margins were not very high & their main customers...the supermarkets were constantly putting downward pressure on prices. They now employ a workforce which must be around 70-80% Polish & Eastern European, without those workers we would be importing all the things they produce.
At least this way the Europeans are contributing, spending money in local communities, paying tax & NI & the company is supporting local farmers & UK suppliers of the other ingredients they need. The whole situation is not as black & white as it sometimes appears