These are created for search engine results when someone types in certain keywords like "Fresh Flowers" or "Buy Flowers Online" or "Valentine's Day Flowers". By definition, search results should contain results containing specific keywords, so even though these are advertisements they are at least pertinent to the search.
I try, when possible, to make my banners as aesthetically pleasing as possible and abstain from annoying special effects. I'm sure you've seen some annoying banners out there that you simply cannot avoid. Yeah, I hate them too. I hope you do not find any of my banners annoying. Rather, I design them as delicious eye candy. And let's hope you click on a few of them out there in the world ;-)