Economic suicide to leave.
IME, the most ardent of 'out' people I've spoken to tend to be either retired, or self employed sole trader/small business type people who are in service industry sector. People who work in business sectors that are regularly dealing with international clients realise we'll be screwed outside the EU. I don't think the general population is really aware of the number of major foreign companies who have manufacturing in the UK because we are in the EU - Nissan, Toyota, Honda, BMW etc. The Japanese companies manufacture here to get around EU quotas, so they're not going to hang around if the UK leaves the EU.
My OH is currently working on a project for a very large International company - they are putting together their detailed plan of action of how to pull their business out of the U.K. if the country leaves the EU. (Bit worrying, as they employ thousands of people). Her opinion is that if these guys are planning to go, all of their major clients will be doing the same thing.
I guess I may be biased, as many years ago I used to work for a Govt Dept that doled out European funding for regeneration, infrastructure and environmental projects - again, because of the lack of positive press coverage, I think the general population are completely unaware of the amount of money the EU contributes to big projects. The sums of money we were dealing with were so massive, most people wouldn't believe it (bilions - just mind bending when I think of it now, especially as none of us had any accounting experience!!)
Something that did strike most of the staff where I worked was the difference in approach that Britain (under Thatcher/Major Govt) took with the EU. The British approach at the time seemed a bit blasé and compromised, in contrast, the Dutch, Belgian, German and French picked the brightest people with solid backgrounds in their respective fields - we had a spot audit done by a couple of senior auditors from Brussels. My boss took them out for an evening meal, and the following morning, he announced to myself and my colleague - "boys, we're f***ed" :)) The EU guys were very sharp, and didn't pull any punches - they were definately not into creating loads of red tape, but were all about efficiency and knowing where every penny of their money was going. The EU auditors both had years of accountancy experience and they were frankly aghast when they found out that our office didn't have an accounting qualification between the 8 of us. (It was shortly after that that I decided I needed a career change.....Rat...sinking ship yada yada )