I commute a mere 9 miles RT a day and I smell the weed no less than twice a week, every week. Smoke coming out of parked cars. Wafting out of moving cars. Guys and gals walking down the middle of the street smoking big fatties. Smoke pouring out the window of a cab at the cab-stand. It's very, very common.

Some of this is coming from the blighted part of town I ride through, true, but a surprising amount of it I'm smelling in the business/commercial section of town. It's not infrequent that it's some dude in a suit who is puffing away at the stoplight in his Altima with the window cracked on his way into the office at 0830.