Is the speaker wearing them? If not you should introduce the word for "that."
Do I understand, then, that this sentence could be (would likely be?) used when referring to the shoes being worn by the person being addressed?
Yes, like this you can ask person about shoes he/she wears. Also shoes might be physically near to people who are talking
I think 'these' and 'those' should both be accepted. There is no indication of where the shoes are in relation to the speaker. They could be here or there. Ці translates as both 'these' and 'those', depending on context.