So, resources are wasted for a line on a map turned into reality with no need.
Ligit humans are no issue. That's those that do before a trip their homework on Visa, accommodation, traffic laws and which sights to visit and whom to meet at which place for business purposes understanding how much and what they can bring into their destination.
The problem is a fraction that knows as well that they give a shit about laws breaking them.
Every good needs a buyer. Not one good meets it's recipient at a boarder, ever.
They meet in stash houses, parking lots, warehouses and offices.
Drugs are not consumed at the boarder ever. They are consumed in bad areas in public, run down real estate, shiny clubs with incredibly bad speakers or offices full of egocentric assholes.
You will score more drugs by hanging out in Manhatten checking for wide pupils to follow the attached feet or ask around where, if taking an anonymous hypothetical bet, most Cocktain is used to also follow up than slowing down traffic in the middle of fucking nowhere..
#MIB