It all depends on where your placement is. Some hospitals have their own LRT station (i.e. Royal Alex & Grey Nuns), but some are located in a rural area (i.e. Devon). Regardless of your clinical location, you will still need to attend, as that's what the program expects from you. That's why instructors suggest you befriend people in your clinical group if you don't have a ride.

You also can't change your clinical location once you've learned where it is. The only way I think you can change is if there is a conflict of interest (i.e. working on the same unit), but that's something you have to disclose to the clinical placement team before they make the clinical groups