Bowing is an essential part of practice. By essential I don't mean that it is something that you have to do "or else...". It is a natural part of the Buddhist path. When we bow, we don't really bow to anything in particular. We might bow to a statue of Buddha. We might bow to empty space. The main point is to bow. Bowing realizes bowing. That doesn't mean that bowing doesn't effect our experience, or that it doesn't effect our path. A Buddha bows. But it's essential not to make it a big deal. When we bow we bow without holding on to "bowing".