This about culture. This kind of behaviour never used to happen in the UK for a number of reasons -
firstly parents and schools properly disciplined children. I'm not talking about corporal punishment btw. I'm talking about being raised from a young age to respect parents and teachers, do as you were told and respect authority and respect others. If the majority are raised like that then they are better behaved. Now there is a culture of 'the child is always right'. They must be allowed to run riot in school, supermarkets, restaurants. They can kick the backs of seats on aeroplanes and be loud and disturbing to others. When I was a child, I was raised to believe that I should stand, being young and healthy, and offer my seat to any older adult. That is the total reverse of culture today. Children run for seats and would be horrified at being expected to stand. Any complaints today about a child's behaviour are met with 'but they are just a child' and an attitude that discipline and criticism (especially criticism) will irreparably damage the child's self esteem. I know not everyone raises children like this but this is now the majority attitude and it has a massive impact. It's like letting a dog piss in the house for years from when it was a puppy; you will struggle getting it to do anything else. It's too late.
second, is social willingness to intervene. This has waned totally for loads of reasons - lack of policing. We all know the police don't even turn up and don't do anything. So who is going to risk their safety of their employees if you know you won't get police back up? That means the security guards don't do anything. Which in turn means the public, who might otherwise come to the aid of a security guard doing their job, don't do anything either.
third, is fear. the lawlessness you see everywhere - this sort of open shop lifting, drug taking, knife crime - means that people are frightened to even speak and just 'tell off' verbally kids even stealing eggs or throwing them at houses. They are frightened they will get attacked or maimed.
fourth is lack of leading from the top by example. We have had a long run of lawless behaviour at the top of society. You may laugh about 'partygate' but ultimately it was the most senior politicians showing a disregard for the law. Same with all the other events - failing to pay tax, leaking info (allegedly) to Epstein - wherever you look there is no good example at the top of society showing quietly day in and day out you obey the law, respect others and their property.
Those I think are the main reasons but it really shows. You don't get people behaving like this so openly lawlessly in many other countries. Shoplifting has always happened but the scale of open, sweeping stuff into bags is unbelievable. I've seen it myself several times having lived years without ever seeing anyone shoplifting.
More police would be a good start dealing with actual crime rather than mucking about with WhatsApp chat groups and social media non-crimes.