I'm not sure, but I think it has something to do with turning lanes or something (i.e. if you're at a major intersection, people turning left might get a blinking green light, then a solid green light for people going right or straight on through).
Driving in BC *is* nuts. Alberta, Ontario, and others are much better. Quebec is all right if you know French, but watch out for some of the other drivers there!!! Like the song says, "...I may not be able to turn right on a red light, but, tabernac!, I can go right through it..."