UK wants to leave the EU for a few reasons, losing money to remain an EU member when our own economy is struggling outside of London. Freedom of movement etc. is a problem, the government gives handouts and dole money to 'asylum seekers' that come to the UK and reject the opportunity to stay in other EU countries (only a problem in the first place because of our welfare state). We can't negotiate these points with the EU, we tried, hence why now we want to leave.
The general public wants to just get it over with and think the best idea would be to negotiate deals with non-EU countries the UK has good relations with, like Canada, where previously we were unable to because of the restrictions the EU has on trade deals between an EU and a non-EU country.
As for losing ALL of the EU benefits, then the EU should lose ALL of the benefits of having the UK in it, like the 39 Billion pounds the EU claims we owe. The EU is being so anal because those running it know if the UK gets a good deal other countries like Italy and Hungary will soon leave, it will give the EU a terrible image.