First of all, let’s make one thing clear: this is not about you. People who post hateful comments are usually angry at Facebook for interrupting their Facebook experience with an ad. They don’t seem to understand that Facebook chooses where and how often to display ads.
You can respond politely and explain how Facebook makes money. You can ignore or delete the post. If you love inflaming the situation, and controversy is your thing, then absolutely follow your instinct and argue with the haters. Personally, we don’t have time or interest in this. However, it can be a useful tactic because the more comments you have on the post, the better—Facebook will see your post as being very popular, and relevant, and will show it more often.
Let’s assume that you want to be civil, though, because your question implies that. You can mitigate the problem by choosing different options for your ads. When advertising and promoting your content, select Current Fans Only instead of Friends of Fans. This way, only the people who already know your product or company will be able to comment.
Sometimes Facebook will automatically promote your content to Current Fans and Friends of Fans. You have the option to delete the Friends of Fans ad units inside your Ads Manager.