I’ll use “xiaojie” when talking to “in-group” people in Taiwan or whom I know from Taiwan (which for me means English speaking people who also speak Chinese to a fair extent). In that kind of situation, “xiaojie” usually is slightly derogatory – the kind of bleached-blond, high-heeled, mini-skirted, overly made-up Taiwanese girl with too much money and free time, accompanied by a lapdog on a leash or in her handbag and trailed by a slightly harried but arrogant looking older man who is usually no prizewinner by his looks.
Other words we would typically mix into English with this group are (with their ordinary meanings, for the most part): shuijiao, guotie, zongzi (probably other food terms as well), qing jia, lihai, baituo, baibai, laoban, lizhang, suozhang, (probably other titles of officials or people), yuanfen, and probably a lot more I can’t think of just now. These seem to be used because even if there’s a close English near equivalent, the English just doesn’t adequately cover the full nuance of meaning in Taiwan in my mind, and since the person I’m talking to knows what this term means from its original context in Chinese, it’s easier to use it in Chinese. Also of course linguistically it gives us the cachet of belonging to the in-group of people who “fit in” (a lot of language choice and code-switching options have to do with group membership and belonging).