I've seen cases where spammers abuse sign-up forms to generate spam (by using the name field for their content). Without server side validation it would be trivial for a malicious user to accomplish this.
I've done Chefs Plate and Good Food here in Toronto, and while they are great, for people like me living in the city, the delivery is not the most convenient aspect.
My local Supermarket chain, could just put up a rack with meal kits, and destroy most of their market.
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