This actually wouldn’t works. Because concentration of exhalated air will depends on the distance between mouth and hole. The only way to exclude surrounding air is to breath inside straw. Vending machines will supply personal straw for each client. That is why everything will be personal and sterile.
This makes sense to use personal straws for each client. I wouldn't use it if everyone will use the same straw
You can see in this video how it will be done, really easy and hygienic procedure.
https://youtu.be/fdiRqMMzLC8
Thank you didn't see this before. Seems easy and practical to me to use with results printed on the good old paper. Nice woman btw