I have two answers to those questions: 1) Yes, in some places, these basic survival activities are highly restricted, or maybe even illegal. And 2) I don’t care.
If it is illegal where you are, that would be a worthy application for civil disobedience. Are we going to let someone keep us from using natural resources to meet our household and neighborhood’s most basic needs, food and water? Oh, and by the way — there are many ways to grow a food garden that looks like an ornamental garden. And, I hear there are people who teach stealth rainwater collection.
Also: Collecting rainwater by turning the ground into a sponge via plants and mulch is a way to collect a huge amount of water where it’s needed most, where most water consumption of a household takes place: the yard. And turning the ground into an absorbent sponge is a lot easier and less expensive than having a bunch of cisterns. Plus it’s not illegal. So you can avoid legal trouble and make life easier for yourself all at once!
And then there’s this: Government and corporate interests are major contributors to drought and famine. If they want to try and prevent us from retro-fitting basic compassion and sanity and ecological common sense into our communities, they don’t have much of a case.