I still dont know how people living there can use bitcoin to purchase food? Bitcoin Credit card?
I don't think they can, as of today.
If this was for real - I don't think it is - then eventually the means would show up. Physical representations of BTC could be used, although they should be discouraged due to counterpart or counterfeit risks.
Something like
Coinapult SMS wallet could work well too. SMS payments thrive in Kenya, I've heard.
Of all nations on Earth, I doubt there's anyone more used with price instability than Zimbabwe. So that shouldn't be as big a problem to them as it would be to others, even because with BTC prices would be mostly falling, making them richer, not the opposite they're are used to.
tl;dr: It would be great for them to do it.
I just don't believe it's going to happen.