Is AdSense on every page of your site necessary?

Well it's been a while since I last posted something. Now I know I'm not a guru and there are a lot of experts on AdSense. But does it make since to have AdSense on every page and is it a good idea to do this?

What got me thinking about this is, I was looking at a catalog I got in the mail you know the ones fulled with low priced products. Well the one I was looking at had these detox patches for the feet and I had never seen anything like this before. So I hit Google and did a search on detox patches for feet.

I clicked on the first site which was a good looking site. It had good graphic, good layout, was nice and clean with a good sales page. You can tell some thought went into it, with some good brief information on it and best of all a buy button mid-way on the page (because don't you just hate some of the sales pages that seem to never end. I know I do because after 5-10 minutes of reading I ready to move on).

Well to get to the point they are selling detox patches and the Google AdSense ads they have on that page are promoting other peoples detox patches. Now I don't know about you, but why would you want to give someone the opportunity to leave your page, possibly losing the sale just to make a few dollars from AdSense. But I guess the thought is if I can't get them one way, make a little the other way.

Good Luck