2002 Honda Accord Stripped Bolt and Oil Pan

I have a 2002 Honda Accord. I went to get the oil changed yesterday and they told me the bolt and oil pan were stripped of the threads and would need to be replaced. When I asked the cause they said the last person to change the oil either put it in at an angle or tightened it too tight. After I told them (Honda Dealer) that they are the only ones to change my oil, they said age of the vehicle is probably the reason. Is this true? I feel like since I am a woman they are trying to take advantage. I told them then there is a 66% chance that they are the ones that caused the problem and they should be responsible for that, but I find it curious that the age of the vehicle didn't come up until AFTER I stated they were the ones that did all the work on my car. Thank You.