Putting any customs considerations to one side, one hopes that the weight realities are accounted somewhere ?
In a numerical sense no. But we're not oblivious to the fact that bottles of booze are still onboard, even though they're not showing on the loadsheet anymore. We rarely max out the thrust reduction leaving an arbitrary margin which, hopefully, consumes any discrepancies. The EFB neatly give us the expected performance, both runway remaining and engine out climb gradients.