Sharing and double standards when it comes to dogs

I have often been told by Dave and Louise how important it is to share, which is why I'm so generous with the Pringles that Louise buys for me; I let Dave have some, I even let him hold the tube.  BUT, I'm starting to think that there are double standards going on; why do I have to share my Pringles when Louise won't share her pillow?  She likes to sit with the pillow when she watches TV, but I like to sit on the pillow when I'm watching her watching TV.  She said it's her pillow because she bought it, but I more than pull my weight as a food disposal unit as well as a cat deterrent and junk mail monitoring system.  

I am going to try and get Louise used to sharing the pillow by looking so comfortable on the pillow that she feels really really bad asking to use it.  Let me know what you think of my 'I'm so comfie, why would you want me to move' look.  The stripey blanket next to where I'm sitting on Louise's pillow is my dog blanket, which Louise is more than welcome to share.

I'm so comfie, why would you want me to move?