Just like in Super Metroid, it's possible to skip zebetites in Zero Mission. It's only really humanly possible for the 1st zebetite, however, and even then it's a 1 frame trick that requires some tricky setup. Video by ZX497 shows it in action:

Skipping the 1st one prevents the 3rd one from spawning as well.

The skip is performed by freezing a rinka close to the floor (make sure you're standing on it), placing a bomb in midair (make sure it's low enough to propel you upwards, but not low enough that it will destroy the frozen rinka), and then unmorphing the same frame the bomb is about to launch you upwards (so roughly when it explodes). This will make you enter a state where you kind of hover above the frozen enemy in midair. Simply hold left to bypass the rinka in this state.

It's potentially useful for any% if you get the trick right away, since it does save 14 missiles, though it takes a while to setup and it's potentially superfluous if you gain enough ammo in the previous Metroid rooms. (EDIT: Since this guide was written, missile route has changed slightly to accomodate this trick, and now it's used in most of higher ranked any% runs.)

The main application is for 9% normal and 9%/10% hard, where zebetites take a while to get through.

Misc:

Decently fast way of setting it up (keep in mind that for low% categories, you don't have hi-jump, so you'll have to improvise a little):

SamTheDigital suggests a slightly modified version where you re-freeze the first red rinka to avoid being bothered by it, should you not get the clip first try:

Skipping all zebetites (TAS only, really):