This is not something I recommend to do. You should be honest with your fans and readers, because they will finally find out, but I noticed on some sites a technique to fake the facebook widget.
It is very simple and most people won’t notice. You take a screenshot of a site with the number of fans you want to show on your website, cut only the widget section, then add it as an image to your site, with a link to your facebook page on it. People who pay attention will notice it, but usually people don’t pay attention to the widget. They will only look at the number of fans you have and they will eventually click on it.
If they ask you why there is an image instead of a widget, you can say that you wanted your webpage to load faster, and connecting to facebook whenever your page loads is an additional connection that you can skip by placing an image with a link on it.
I am not doing this and I do not recommend you to do this. Just wanted to let you know that it is possible for others to make you to think that they have tens of thousand of fans when they actually have only few.