We definitely see outflows of material along the equator: disk winds! In fact, we think that in protoplanetary disks and accreting black holes, you can have winds and jets launched by the same magnetocentrifugal mechanism, where magnetic field lines coming out of the surface of the disk rotate while "anchored" to the surface and material is driven out centrifugally along the magnetic field line. The jet is then a special case where the opening angle of the global magnetic field closes around the rotation axis. This is not the only mechanism for driving jets, and certainly not the only way off driving winds though.

The key here is that jets are strongly thought to be a fundamentally magnetic process, where the strong magnetic field of the accretion disk near the accreting object interacts with the fastest rotating material in the disk. The magnetic field geometry of the disk is driven entirely by the rotation of ionized gas in the disk, so the close connection to the rotation axis of the disk is not incidental. Curiously, the jet does not have to be perfectly aligned, and the jet may be misaligned or begin precessing.

Another way to think about it is that everything in the disk is basically axially symmetric around the rotation axis. When the disk spits out material, it does the same in the form of winds. Jets are a special case of this.