@Jalima
The EU regulations were changed a couple of years ago and the UK got a favourable deal. No thanks to Farage, who was on the EU Fishing Commission, but to the TV chef, Hugh Fearnley-Whittingstall. The fishermen's biggest grievance was discards, which have been abandoned, and quotas. The UK has generous quotas and it's the responsibility of the UK government, not the EU, to allocate them.
Unfortunately for small trawler owners, they've been overtaken by super-trawlers, which scoop up all the fish for miles and then process them before they've even landed. They and the processing plants can't compete, but that's 'progress' not the EU.
If there aren't any quotas, fishing stocks will disappear and there won't be any fish for future generations. This has already happened with herring.
Fishermen would be cutting off their noses to vote Leave. As you mention, they export their catch to the EU and many of the traditional fishing areas receive huge amounts of EU aid to develop other businesses.
To be honest, fishermen have always had to eke out a living. My gt grandfather came from a big fishing family in the North East and when I was doing research into my family history, I was amazed how poor they were. Many of them also worked as builders, so they had work outside the fishing season, and lived in quite squalid conditions.
I think Geldof was protesting at Farage's hypocrisy.