Independent worker, but forced to stay opening-close hours

I work at this certain tattoo shop and have been forced to stay from 11am sharp to 7pm sharp at the shop, even if I do not have any appointments during that day or finished all of them. How usual is this in tattoo shops and is that even legal since I am not contracted.

• I work at the shop by commission (the owner gives our share every week by e-transfer and we do not have access to the calculations that she makes)

edit: Thank you everyone for your insights, I think my choice is clear now.