Yes you can boost your WiFi signal. What you will find in most cases is that WiFi signal strength is not going to be your issue. Limited bandwidth when connecting to the campgrounds WiFi is where you will have issues. In my experience campgrounds have inadequate bandwidth when they begin to fill their sites.
The booster sometimes helps, but the issue typically is crappy Internet bandwidth to the campground. No booster will boost that. It just sometimes helps you get a connection to that crappy network.
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