Carbon filter insert?

http://m.ebay.com/itm/120833932336

Would something like this reduce the smell a little bit? Don't really care that it smells just wanna reduce the smell a little.

That is for intake, exhaust = smell.

So I can't stick it on my exhaust?

Sure you can, but you may find that they don't last very long. Carbon doesn't work "just a bit", it will strip all the smell it can handle for the air flow, then just stop working once it cannot take any more. For the cost of them, i suggest you get a can filter and just remove the smell completely. It makes the experience of opening your tent and taking a deep breath that much better as you are not used to the smell being in the air all the time