I hope Elon the best, but I wonder if that is happening here. SpaceX is going to sell Internet, do fast air travel, do space tourism, . . . . Same with Tesla: we aren't just a car company, we're a battery company! There is a hyperloop and a digging company and solar rooftops. I think it's true there are many opportunities, and history has had its conglomerates like GE, but there is risk in losing your focus.
Still, I'm thrilled he is pushing us forward!
It's pretty clear that SpaceX is in the reusable rocket business. By your logic, Boeing didn't have focus, because they built seaplanes, flying boats, fighters, cargo planes, and passenger planes. (This is what they did, in the order that they did it.) They apparently had at least 5 business models. Whoops. I guess they didn't have a business model!
If you can launch rockets capable of re-entry and reuse and need to finance building rockets to go to Mars, you can build rockets for cross-continental travel.
It's not like SpaceX is building a smartphone. They're building in their core competencies.