Some minor issues

I don’t get this. E-commerce is like 10/15 years old, and still “professional” websites are making basic mistakes.
Like this example below, on the Sherpa website. Sherpa is an organization selling tickets to shows and events, and luckily they understand internet is an important sales channel.

However, I’m very stunned when I see things like this:

Apparently I can’t order more than 1 ticket of the main category (the one with the most tickets available) at the same time. For starters this is absurd. It just can’t be I have to order 2 tickets separately (and go 2 times trough the process, pay 2 times postage, get 2 seats not next to each other, ..). This is a real show stopper and business killer. But secondly: what a sucky way to communicate errors. For those not understanding Dutch: the error message is not well formed and not very user friendly. Not explained why, not explained what you should do to order more, ..

Really, I don’t get this. This is supposed to be core business. I suggest a drastic usability review. I think I remember the registration process wasn’t very smooth either.

So back to the title: How is e-commerce supposed to grow up? This is a bottom-line question. I don’t know what the Sherpa site have cost. Being in the business myself I have sort of an idea, and I guarantee you: it’s not cheap. It shouldn’t be cheap though. But I can’t understand, why in an expensive website, user experience and usability isn’t well thought and used as a presumption in development.