Even if you do not typically put your feet into the toe kicks recess you still need it. After a couple of times bumping into the cabinet without a toe kick you will start standing farther back. That means leaning over more and therefore straining your back, shoulders and arms and generally making things uncomfortable for yourself.
If you need further convincing of the importance of a toe kick, then place a board across or box inside the toe kick in your kitchen or bathroom, thereby eliminating the toe kick. Try it for a week. You will probably take the blocking out within two days.
Even with a toe kick you can still have problems. If your toe kick dimensions are wrong you should consider modifying the cabinets to to fix the situations.