[neverokay]

There's one scheduled, and paid for, to launch fairly soon, but with no spare capacity

Stupid question of the day, can we not just force jam a bunch of astronauts into it?

[Am4TIfIsER0ppos]

The police complain if you have people riding on your lap in a car. Imagine what NASA thinks of that for a space pod.

[dessimus]

There's no way the NASA flight director wants to deal with the paperwork for elevated vital data of those whose laps were occupied: "Sir, the whole craft was vibrating, not to mention these flight suits are ...restricting..."

[aejm]

Yes absolutely. SpaceX Dragon is cleared to seat up to, I believe, four extra astronauts in an emergency.

[falcolas]

Weight is probably a big one.

Slowing things down requires energy (or the dispersion of energy) and that amount of energy is directly related to the weight.

Plus breathing gases, waste management, and any other required consumables.