They were a lot further developed than the colonies at that point. There was a whole bunch further west that hadn’t even been tapped into. They fought two wars with us over the colonies because they wanted to get their hands on the Celtics and Patriots dynasties.
To set the record straight, the primary causes of the War of 1812 were British interference with American trade (Orders-in-Council), the impressment (forced conscription) of U.S. sailors into the Royal Navy, and American desires for territorial expansion, particularly into Canada, fueled by "War Hawks" who also pointed to British support for Native American resistance on the frontier. These issues, rooted in the larger Napoleonic Wars, challenged U.S. sovereignty and economic interests, leading to a declaration of war against Great Britain. It was not the British desire to retake its former colonies.