There's a couple of things that bug me about how our dear local theater treats technology as an afterthought, and I have to get that out now.
First, there's their newsletter that you can subscribe to. Great thing, that, very informative. But it contains a very strange tombola system for two tickets each week: It is not a random drawing from the replies they get, but rather, it is the first email they get that wins the prize. Evidently, they don't have a clue as to how email distribution works, otherwise they wouldn't pretend same chances for every participant. That's probably not even legal.
Far more serious however are the shortcomings of the online ticket ordering system. Theater Basel seems to be doing that through an unknown agent called eventris. According to their site, eventris receives a 10% commission on tickets ordered online. But the user gets a CHF 5 System Gebühr (sic!) slapped on his bill, without comment or explanation. What's more, tickets bought online cannot be refunded or exchanged, which is another disadvantage in comparison with the brick & mortar Billettkasse. And if all that hasn't discouraged you sufficiently yet, the ordering site looks and feels entirely unprofessional. So, evidently, the people responsible for this just couldn't care less and obviously do not want to have their b&m channel cannibalised while still wanting to keep up appearances of being in line with today's best practice.
Naturally, they are entirely incommunicado about all this ...