In reply to kylo-342:
When I lived in Switzerland (two years ago now - things might have changed) that wasn't the case. They had just introduced a system where you could buy cheaper tickets in advance, though only on major intercity routes.
The ticket part of the SBB (swiss trains) website isn't working for me, but I suggest you have a look at the supersaver tab under 'travelcards and tickets' when it's working again. (There is an english version of the website)