No they aren't all Vietnamese.
As for the person who asked the difference. As someone who has received manicures/pedicures every two weeks for the past 12 years, here you go from my observations in my area (YMMV):
1. Vietnamese places are generally walk-ins and will blatantly lie to you about the wait time so you won't go to another salon. Some take appointments, but if they have a customer in that seat, even with an appointment you will be waiting. Most non-Vietnamese places do not take walk-ins and are appointment only. 99% of the time when you arrive the tech is ready for you.
2. Vietnamese places recommend "getting a new set" of acrylic nails every month or so. This is to generate more revenue because full sets cost a lot more and give them more profit than a fill. Non-Vietnamese places actually take enough care of your nails that you don't need a full set - well hardly ever. I think the last time I got a full set was over 3 years ago.
3. Vietnamese places have literally cut my fingers (one salon it was the same lady about 4 visits straight before I complained and never went back) and left me bleeding because they are in such a hurry to get done. I understand a nick every once in awhile is inevitable but the amount of time I have been cut at a Vietnamese salon vs. non-Vietnamese salon tells me they need to slow down.
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