Sainsburys have always had problems with certain Schoolchildren. I recall seeing a couple of teenage boys in there one day who took a can of beer each and walked around drinking it then dumped the empty cans on a shelf. I reported it to a security man who collared them and made them pick up the cans and take them to a checkout and pay for them.

Back in the days of MacDonalds FH Boys and Sydenham Girls were banned in there at lunchtimes. We were in there one day when a whole crowd of them came in and were being generally disruptive. Presumably the school was informed as the school minibus turned up with about 6 teachers and the kids scattered, hiding in the toilets etc. they were rounded up and taken back to school. I presume the ban was imposed by the school as well as McD's due to the reaction.