Unstable highchair injures baby

I went to eat out with my family and I saw that a family was using a high chair so I requested one from our waiter. I proceed to put my 9 month old baby in the high chair and after a good 20-30 minutes, the chair collapses while my baby is in it, she fell hard on the ground, hitting her head against the steel of the table. I am still furious that this happened. If your waiters do not know how to assemble the chairs correctly, please train them to do so.