Lolz, Hispanic people talking is usually yelling insanely when heard by a gringo. Also, if he's anything like me, if you take away my morning toke, which has been my ritual to keep me from being a really nasty mean person for nearly 10 years now, I will most likely be a really nasty person.
It's about respect, you denying that you took it was most likely a greater form of disrespect than taking it. You should have just said "yeah, i was fiending I apologize I'll replace it". Lolz MS cats (especially older ones with a fam) wouldn't wanna go down for life because of what amounts to a few dollars.
OR
YOU CAN SAY: Yeah dude I smoked your weed, if I beat you in FIFA I don't have to pay you. If you win I have to buy you 2x the amount of weed I smoked. No one can play as Brazil though