Heavy payloads and ones destined for geostationary orbit currently need a drone ship, whereas lighter payloads or ones for low orbit can return to the launch site.

I'm not sure how much the drone ship launches deviate in a north/south or east/west direction for ship landings (couldn't find a map). The boosters have a fairly significant ability to maneuver, and a fixed platform may offer enough benefits to slightly limit payload sizes. Falcon Heavy will also help there.