People can and do trade anything for anything.  For example, loaning out tools to a neighbor in return for a future favor moving furniture is a valid trade.  What tends to rise to the level of money is the most easily traded and most accepted good or commodity.  So while your weed & beer exchange was definitely a trade in the economic sense for plumbing services, most people would not say it has risen to the level of money.

Bitcoin balances in the global account book (block chain) is a traded commodity also, but is still working on reaching widespread use as money.  Ease of trade and general acceptability are not there yet, though they have been improving quite rapidly.