It still doesn't make any sense - why did Maxis do that anyways?
There is some sense in it:
When you call transportation, you get the option "invite sim", and then 3 sub-actions are performed: the sim call somebody, get a message that he is not available (if positive), and call the taxi company back to arrange the drive.
When you call taxi, no sub-actions are performed.
It's like the programmer wrote: if A then Routine a, if B then Routine b, and threw it to the "trash"...
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