For a while I used a Nikkormat FS to practice guessing light since it doesn't have a meter. Most MF cameras don't have a meter either, but bulk rolled 35mm was a lot cheaper per frame. There are still times where a meter is necessary like very limited dynamic range (reversal film), very expensive shots (8x10), or shots you can't easily recreate tomorrow (solar eclipse). Nonetheless, I feel it was useful to go through that process because it also makes me more confident in what my meter says,