"Can I get some soy sauce?"
English often phrases requests as questions. Different languages express things in different ways. Don't expect things to translate neatly. For example, in Russian, there is no direct translation for 'to have.' The phrase used means literally 'it exists next to ___' but it is used to mean 'to have' and is translated as 'to have.'
"Kudasai (下さい) is the imperative form (命令形) of the verb kudasaru, which is the humble/polite form of describing someone giving (literally, passing down) something to you."
"KUDASAI is not necessarily "please". When it's used after the particle O, it means "please give me something"
So, I tend to think of ください as meaning "please give me" something. The "give me" is implied in English rather than stated explicitly but it is there as a request.
In some parts of the English speaking world, it's not uncommon to request things by saying, "Can I get some... ? although I'd probably add please all the same.