Granville Street around Smithe is a great place to people watch.
You have a blend of hipster & alternative boutiques next to the nightclubs, pubs, theatres, and greasy dollar pizza shops. The McDonald's and Burger King often have street kids hanging out front and down the road are the budget hotels and the backpacker hostels. Then there are the businesses from another era: greasy spoon diners, pawn shops, and porn shops.
Granville's really trying hard to gentrify, but it's not there yet. Needless to say, it makes for great people watching.
p.s. Check out the people on the left in the last photo... priceless!