There was great potential for that then as well. Joining required the UK to give up exclusive fishing rights in its own waters and put up tariffs to its Commonwealth trading partners. That the UK did so without much of a fuss is a matter of shame for the country, the trade disruption had great impact in countries that depended on the trade. The Common Agricultural Policy was cemented in to prepare for UK arrival as well, so guaranteeing transfer of wealth from UK into France, an almost direct subsidy of French agriculture. This was the basis on which Margaret Thatcher went all obstinate to get a British rebate in the early 80s.