You could indeed do programming on a Macbook, or a PC, or netbook or whatever.
If you have one.
The point of the Raspi is that people who wouldn't normally have programming access to a device can have a cheap device for programming.
[Many home PC's and certainly a almost all school PC's are pretty locked down and prevent programming usage.]
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I own the world’s worst thesaurus. Not only is it awful, it’s awful."