Is it wrong to let my 4-year-old son go to the shop on his own?

"He's quite sensible"

One mum has come under fire after asking if she could send her 4-year-old to the shop on his own. She explained that her local shop is only 200 yards away, but fellow parents couldn't believe she was even considering it. The mum also said that the shop workers know her son well so she completely trusts him. "Today, I thought about letting him go to the shop on his own. We live on a busy road, but there's a wide pavement, and he wouldn't have to cross the road. "He's quite sensible," she said. "He seems very young, but he's quite capable of going into a shop and buying things on his own." The mum said her son has done this before while she waits outside or in her car. They've been doing this for around a year, she explained. "Is he too young to walk there and back on his own?" The mum may think it is okay but others were stunned by her idea. One mum said she would never ever let a 4-year-old do that. Another added, "No. not a chance. What on earth would he be going to the shops for at that age?" "I would say slightly too young. Could you watch him all of the way? (my daughter would be fine in the shop on her own, she's 5. I would worry if she saw a friend/cute kitten etc on the other side of the busy road and decided to risk it)" Another parent pointed out that 4-year-olds don't have a good understanding of risk. "4-year-old kids have no real concept of risk. Also, he would not know how to react/respond if something even slightly untoward happened." Do you agree with the mum or is her son way too young?