It depends. If it was random popular charity, most likely not. If it was charity I do support anyway and that I believe is doing a great job at managing money and sharing support, I would at least consider it. I believe me being not comfortable for few minutes is worth less than all meds and food that can be bought for shelters, etc.

With this being said, I see it more and more recently, popular, multi-million companies claiming they will give money for charity if people post with specific hashtags or do very specific photos, etc. As much as I consider it a innovative way to get some bonus money to charities, the way companies use it for self promotion is so disrespectful for all people and animals that need help. And even if they do donate, they often get money back from all free advertisement people do for their products.