Good Decent Cheap rental but with dishonest staff

Please note that the staff here at the DMK counter has a tendency to be dishonest. I may be jumping to conclusions a bit too early but I parked the car upon return at the designated return spot and went to return the car. Due to some miscommunication, I ended up having to leave the car there and go ahead with my flight check in first. After I had checked in, I returned to collect my hand carry which I had left in the car I found out that Snacks which I had purchased to bring back home went missing from the car. After confronting the staff, they had the audacity to accuse my girlfriend who was standing beside me. They accused that she had in fact been the one who had taken the items from the car when she was with me this period of time. To me, the losing of snacks is a small issue. The big issue is that, while the car was at the company’s parking lot, I still manage to have someone open a locked car and taken those items. Snacks are cheap but what if it had been an expensive or important item like identification or money? And instead of taking responsibility. The hertz rental guys accused my partner of taking the items for herself. The only reason that I didn’t call the police was due to the fact that I had a plane to catch. Would never go back to this outlet and would NOT RECCOMEND IT. Shall say something about the car, big ,clean and spacious with a very powerful aircon. That’s about the only good things. The speaker was spoilt, the fuel needle is spoilt(had just topped up full max tank before coming to the airport, but the needle refused to go higher than mid first marker, causing me to pay an additional 525 baht for them to top up to full max tank for me which I already had done.