As for kettles, all campers should know that domestic kettles are a No-No, with most sites providing 6A, some newer ones 10A
Use a gas kettle. I can get away without leccy, I'm sure everyone else can to - its only a weekend. I will have to use the inverter to blow up my airbed though
Iirc TB all UK sites, unless stated, provide 16A, European sites, like france, belguim etc provide 6A. You are correct that domestic kettles are to high unless you use a low wattage kettle like 750 watts which is perfectly ok to use at a UK site. Anything higher than 1000 watts you need to be carefull that you don't overload the circuit as it can be tripped out. I only know that because my father has been using UK site's for the past 4 years and also goes abroad three times a year as well.
Not trying to put anyones nose out of joint or anything but this is what I have been told, plus the sites I have been to as well have all been providing 16A.
Paul