Nothing odd about it. Type "green and yellow polka-dotted pink footballs" into your Google toolbar and look at the ads on the right side that show up.
I guess you dont understand how Google Ads work. This isnt something you type into google. These are ads that come on on your website (ads you get paid for hosting). They are supposed to match the type of website you have. If I own a website about mustangs, only cars and mustangs are going to show on the google ad, or whatever else you signed up for when you joined the affiliate program. I know, i use them.