Hi,
I still feel obliged to reply because I don't share your point of view and I believe that most people don't. So I just want to explain why it's like that, because there are reasons (like I started to explain in my previous message).
Coupons are all over the place since long ago. But in the 15 years I've been using Internet, not even once have I used several coupons when purchasing something online, even though I purchase a lot of stuff online, and use coupons now and then. And a lot of shopping carts don't support that by default, or at all. So I don't see how someone can expect that a shopping cart software would normally support that by default if not mentioned (and we don't mention that we do). In fact, when I developed HikaShop, I didn't even thought that multiple coupons would be needed at all, and thus the system wasn't made to support it easily in the future, which is why it's not done already.
And each time someone asked us, we always answered that it's not yet possible and that you can use AWOCoupon for that. To continue with the analogy, Joomla doesn't mention all the features it doesn't have, only the ones it has, and like us, it has a place which lists third party extensions for extra features.
Of course, I thank you for your feedback. It's always valuable to hear what others have to say.