I worked in Subway for a week.
I was the only first language English person there, including the managers.
They took off my pay for food and for breaks and when I left my pay was a lot less than I was under the impression that I was getting.
Most of what I did for that week was stand at the end taking orders and trying to convey them to the rest of the non-english staff.
For £4.55 ph? No thanks!