Lots of gun stores have already sent in their newly banned guns for destruction. That was the first "phase" I guess you could say of destroying everything to do with a firearms industry in Canada. Apparently a couple of bigger stores actually spearheaded the idea, so that they could hopefully get reimbursed for whatever inventory they were turning in. And yes, the government wouldn't have too hard a time figuring out exactly what stores have, so there's not much option but to comply for them. Same with people that have formerly restricted guns that are now prohibited, unfortunately the government knows exactly who has what when it comes to AR's and a bunch of other semi auto rifles with barrels shorter than 18.5".What do you mean by "retailers"??
If they have a business license, insurance and bank accounts they will comply or be shut down and then have everything confiscated.
Kristian