These events have been shown to be very rare, and the costs would greatly outweigh the benefits (for the time being).
The cheapest piece of equipment was the stand the FOUPS come down and rest on. From memory, that was easily 5 figures, perhaps low 6. Every other piece of processing equipment was insanely more expensive.
Queuing theory is an active field of research with great applications in how wafer processing. The total process has to be looked at. Wafer priority, wafer value, planning preventative maintenance on the machines, etc. could all be taken into consideration when scheduling when wafers will run.
Retrofitting every "robot" that grabs FOUPS for a much heavier load, upgrading the tracks if needed, replacing every single FOUP, adjusting factory flow and inventory holding areas, doing qualifying trials on the FOUPS (to make sure they're functioning correctly and not leaking), etc. are considerable expense.
Prioritization of wafers and timing the preceding step so the required machine is certain to be ready in the window would yield better results from a strict business ROI perspective.