Sure, I've clicked on context sensitive banner ads numerous times in the past. I've even bought some of the products, but ONLY after leaving the initial site and researching the item further. If the item pans out as good quality for the money, I come back and buy it. sometimes, I just use them for ideas and end up buying something else, possibly inspired by the click ad's products.
I used AH quite a bit during my home theater construction (still not complete aesthetically, but fully functional), and will continue to use the site. It makes a GREAT learning and jump off point to get down to the nitty-gritty regarding almost any aspect of AV and HT.
Thanks to all of you who've posted over the years, your posts were read, digested, processed and resulted in my now having built a very, very nice system for amazingly little cash.
Jeff