I work as a lot associate, and one of my responsibilities is to organize and take all of the carts into the store. I know that in Islam, if we damage someone else's property, we are obliged to pay for it, but what if the damage is extremely minor and minute, to the point that the owner would probably never notice it, unless I explicitly pointed it out to them, and that, in a sense, they agreed to park in an active area? There are two circumstances in particular:
1) I was pushing the cart in a narrow pathway and slightly smudged the vehicle, and it is almost guaranteed that the owner will probably never notice it (it was a very small smudge mark at the bottom of the vehicle, and the vehicle already had other blemishes.
2) I was moving a large cart, and a pebble that was stuck under the tire flew out from underneath due to me moving the cart, and the pebble bounced off the cement hitting the person's vehicle, taking off an extremely small amount of paint which is barely even noticeable amongst other blemishes of the vehicle. Also, if the damages are actually noticeable, I refer the customer to the manager, who will compensate the customer for the accidental damage, but in the case of such minor and minute damage, I highly doubt the store will even compensate the customer for it. Since I was not able to talk to the customers about the minor damages, should I pay the amount in charity on their behalf, even in the second scenario, where I had absolutely no control over the pebble flying out and I was just simply pushing the cart? Would it just be better to not tell them since the damage is not worthy of mention and given that this may cause unnecessary trouble if I tell them? And if I am going to give charity to compensate for it, should I pay the amount which they would have payed the auto-body shop (which is excessive and not the actual pricing for the repair) or the actual/literal amount of money that they would need to remove the minute blemish?

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.

As long as the damage is insignificant and mostly unnoticeable, there is no need to inform the owners of those cars of what happened, and you are not required to offer charity on their behalf. However, if you caused real, substantial damage to the car, then you have to inform the owner so that he gets the due compensation. It is impermissible for you to offer the value of the compensation in charity on his behalf as long as you can reach him directly.

Allah knows best.