disclaimer - romanian here :)
if by tech you think of pure programming (of which romania tends to have tons abroad and locally) I can reassure you that wages in bucharest/cluj - one of the biggest cities are on par with london slalaries. Yes! you heard right, on par although a typical salary in romania doesn't really go above 300 EUR a month net, a coder earns easy 1-2-3-4k / month net depending on experience. I will let you calculate how much that is in pounds/year before tax so you can compare. also, the cost of living is much much lower there. its a coder's paradise right now there. they can buy an apartment within 2-3 years without any mortgage.
so no reason for them to come to GB
the point is - we don't always just pick strawberries or wash cars, there are a lot of us who also code and even earn better there than here