This is not normal behavior. The normal crash should be something regarding the RAM being exhausted (a 32bit wine limitation). I am using the Crosstie current as of launch of Draenor when I reinstalled all of BNET into a fresh bottle (screwed with alot during the making of Diablo 3 work), and I only have issues if I game and run out of RAM in the aforementioned crash case. 64 bit works, but is very slow (half framerate and very erratic at best). All I did was copy the bottle and set it to Win7 x64. There is still alot of fixing I need to do there.
My best advice would be to rescan your game files in BNET and check them for corruption, that has happened to be the case for me in odd cases. Also, when you are going to be idle for a long period of time, it would be also helpful to run Memtest86 for a good day to see if this is a RAM issue. I had a system a few years ago that was getting very wonky on just a couple applications and it turned out to be a bad RAM module. Yanking that stick made all the difference. I bring that up because diagnosing Wine issues can feel like a black art, and a simple thing like a bad RAM module is a lot easier to troubleshoot (run Memtest for a good long time and see if it pukes errors out).
Other ideas are to make sure you are on the latest kernel that your distro(s) released, and the latest NVIDIA/AMD GPU drivers (if applicable). The open source ones generally come along for the ride in each kernel release, so if you are on those a simple kernel update should fix that.
And out of curiousity, is it just WoW that is giving you grief? Only wine?