I have put surge protectors in the same class as chicken soup, it can't hurt.
But their usefulness is still open to debate.
Sure it is handy to know that the electrical box you plug into is wired correctly, but what if it is not? I have selected alternate spots when they were available. However, if it is a popular CG and an alternate spot is not available am I going to leave? Probably not, I will just plug in and see if it powers the TT like everybody else did.
Just how many Joules of protection do you need, 1000, 3000, 5000, 10,000? who knows? A Joule is 1/3600 of a watt hour so it is a unit of power. Just how many Joules have snuck down my shore power before I bought a surge protector I do not know. How many have snuck down my line after I plugged into the surge protector I do not know that either.
What is the protector protecting? The Microwave and TV are the only items that would have sensitive electronics on the 120 volt line. The frig and water heater electronic controls are 12 volt. They both use 120 volt resistive elements and are not typically bothered by line transients.
So like must folks, I plug in my surge suppressor and rest safe and secure in the knowledge that my shore power line is Joule free.
If a lighting bolt strikes it will not even make a good fuse.