Whatalark is spot on. Theft is appropriation of
property. In a shop that means leaving without paying, as long as you do not damage the goods or alter them (such as swapping price tags) then there is no theft.
A law student who knew this once went around a shop stuffing his pockets with things, before he left they stopped him & accused him of shoplifting. As he had not left the shop the shopkeeper was in the wrong & the student sued them for slander & won. So that is why shopkeepers have to wait until the person leaves before they can do anything.
However Singapore law is probably different although it is based on UK law, so don't quote me.
I thought the yellow ribbon campaign was more about encouraging employers to employ ex cons, give them a second chance in society, as opposed to carte blanch 'get out of jail free' affair. But again I may be wrong.
If you want real legal advice you will have to pay for a lawyer.
"An intelligent man is sometimes forced to be drunk to spend time with his fools."
Hemingway