Zahavasdad, why is that a problem. First of all, the drivers are almost certainly gentiles. Secondly, it is pikuach nefesh as there are elderly and unfirm peopel who will not be able to get their meds, not to mention the fact that an ambulance might need to get through. Rav Shlomo Zalman Auerbach allowed using the electric company’s electricity on Shabbat even though Jews might fix problems because of the consideration of elderly, infirm, babies, etc.
