Yip, but defining a list of essential items is impossible because essential is different to everyone else.
Should someone be able to replace a lightbulb during this time if it blows - I'd say yes
Should chocolates, chips and soft drinks be considered an essential item? I'd say no
Should I be able to replace my car battery, I'd say yes
All barbers and hairdressers are closed, yet 2 of the Clicks stores I've been to won't allow you to buy hair trimmers - but you can buy hair dye
Chocolates and soft drinks are bring in more foot traffic than what car batteries would, so using the amount of traffic as the reason does not fit all the examples.
It's a tough job for the government for sure, but at the end of the day the thread title says it all.