Yeah, that's what I was getting at - in CI I can see it, but in local dev it would seem surprising to need more than the free-with-authentication quota.
That said, if your CI needs more, it's probably time to invest in a paid account if you can, and certainly if you're commercial.
You can use the GitLab Dependency Proxy for caching images from DockerHub, it's pretty straightforward to pull cached images:
I can imagine that this affects those sorts of operations.