In Indycar each car is considered a team. The cars are worked on during sessions in the pit lane not garages next to the pit lane. That’s the big one. There are fueling rig considerations. Team are crewed separately. It’s a different animal.
You don’t need a pit stall to practice and qualify. You can do your work behind the wall. Might not be ideal, but it’s possible. A system could be worked out to not unduly benefit some competitors over others at the smaller tracks.