I'm presently in a camp site with a very strong wifi signal. Nonetheless, by late morning, as more and more people get online, my computer just spins its wheels.
I mention this because a repeater/extender isn't going to help this situation. It's a problem of campground bandwidth, not wifi signal strength.
So, that's when I get out my mobile wifi hot spot and use my data.
BTW, I do carry a Amped repeater with me for situations where I don't have a strong CG signal. It does help in those cases, as long as it can get at least 2 bars to boost up to 5 bars. But it can't do anything with just 1 bar.