Ian,
Have stopped for the time being due to fleet cleans etc, have only ever been stopped by security at ASDA stores as they have a policy regarding leaflets round my area,train stations no problems, tesco's no problem if you speak to the managers first same for the multi's, same for factory car parks speak to the transport managers first prior to a drop, 6 out of 10 times you will secure a couple of jobs prior to even putting a leaflet on a windscreen

Malky