It's a bit hard to read, but the item in German lists and costs all the parts which a repairer has quoted as required for the car. It would appear that the bill is for a new parts including parking sensors, the various trim inserts, painting it and labour plus 19% MWST (German VAT tax)...........

You (the OP and several others ) might think that this sort of damage is just normal wear and tear, and in the US it probably would be classed as such, but European rental agencies disagree as this sort of damage has to be fixed before they sell the car on or return it at the end of the lease. And if you think Hertz is picky, try Enterprise, who are even more fastidious.