As a small business owner, I can totally appreciate preferring cash over plastic (that 3% adds up!). I'm sure that's doubly so if you are living on an island with ridiculous banking (non) service!
If only we could feel safe enough to travel with wads of bills on our boats with flimsy locks and no way to defend ourselves. My machete and speargun skills don't get enough practice.
You don’t have to worry about bringing loads cash as long as you anchor in a designated “Crime Free Zone”