Worse, all they did was redirect who gets the disposable income back to downtown restaurants and landlords. Not like the money wasn’t being spent elsewhere. And they did it at the expense of the environment and everyone else’s time. It literally did no good for the economy, it just helped specific businesses. And how often have we heard that it is not the business of the government to pick winners and losers? Let the downtown cores and commutes die. Businesses elsewhere will thrive, and the core will become something new.
Do you need a receipt? I usually pick up my incandescent light bulbs in the weird sizes (appliance bulbs, etc) at Dollarama, but I don’t bother to keep receipts for small disposable items.
Edit: looks like this was answered below and the answer is no proof of purchase is required. Thank you!