I suspect your friend may have been talking about the Common Agricultural Policy. This is the EU's long cherished policy, which through it;s high tariffs keeps food prices artificially high for us and discriminates against African and other third world farmers. I'm surprised that this doesn't seem to bother the "progressives" on the Remain side especially with them being so educated and tolerant compared to us Brexiteers who are so thick, bigoted and racist.
Anyway the good news for your friend, Africa and the rest of us is, even if we have to resort to an EEA arrangement like Norway we will be out of CAP and can remove such tariffs.