Ugh.
These are, quite possibly the most loathed words I could see in my Facebook Feed. I despise them more than I can possibly explain.
I am not sure what the "regular" repost rates are for a facebook post, but I am quite certain something like this DOES NOT help the number go up. I would be even more excited to find out a statement like this actually LOWERS the repost rate.
When a comedian tells a joke, they don't ask you to laugh at the end. If you think it's funny, you laugh. If I agree with your post, and find it "share-worthy" I will share it - whether or not you encourage me to do so.
To infer I disagree simply because I didn't share your damn post it ignorant and arrogant on your part. If you want me to repost something, make it interesting, funny, controversial, poignant or some other relevant factor.
If I agree with your cause, I'll share it. If I like your meme, I'll share it. If I disagree with whatever you said, I will add my comment and share it. Stop telling me I have to share if I agree.
Share this if you agree with me, but 99% of you won't anyway.