The legs are splayed a bit, but it still seems to me that most of the weight is placed in a downward force on the legs themselves. Not the joints. As for the screws, they are holding the weight horizontaly, not vertically. So there's no danger of the screws pulling out. It's all about the shear strength of the screw, not the holding power of the threads.
It seems like a pretty sound design to me.
A piece connecting the front and back legs, down low would add a lot of strength, but probably take away from the overall esthetic.