Sorry but I don't get how you don't understand what he's saying.

He has no idead weed is so expensive in the United States. $70 for 3.5g is the equivelent of £40 for an 3.5 bit in the UK if you take into account exchange rates. This he thinks is a rip off ( to expensive) as he pays £15 or £20 for weed depending on quality ($25/$30).