At least you can use the bis key. My fat fingers simply will not fit on the thing on anything smaller than a baritone, and it's even pretty iffy there. I've given up on anything but the side key or the (horror of horrors to saxophone players) classic to clarinettists everywhere •oo|•oo.
What about Bb to C? What sense does a "default" automatic Bb make when playing in keys without flats? What Greg says makes sense, but what he leaves out is important too. I guess that I am just a stick in the mud traditionalist, but Larry Teal's explanation that each Bb fingering has its advantages in certain note combinations makes perfect sense to me. It is not that hard to become adept at using the best fingering in each circumstance.