Outsiders promoting own business inside Dros

Am not happy with the service that l got from Dros Canal Walk.

We come to the restaurant every Sunday as its family day out but the issue of outside patrons coming to sell their items inside the restaurant is not on. I did bring it to the manager(Patrick) who then told me its allowed .

So how does management allow people to come sell inside and mind you we eating and they standing and selling stuff.

Please let me know if its part of the company policy as it serves as a disturbance