They could but considering the Leave campaign and the remain campaign said repeatedly a leave vote meant leaving single/internal market combined with the central leave campaign theme of 'taking back control' they would be wrong. It's like Remain winnning but people arguing a rabidly anti EU UKIP agenda was what the remainers voted for ...
Total rubbish. Daniel Hannan who has been one of the prominent Leave campaigners for years (longer than Farage) was in favour of remaining in EFTA (ie a customs union). Michael Gove, another leading campaigner for Brexit, also argued for staying in EFTA and as for Farage himself ... "Wouldn't it be terrible if we were really like Norway and Switzerland? Really? They're rich. They're happy. They're self-governing"
There are loads of examples of Brexiters saying something similar, stop trying to rewrite history