At top of my uBlock Origin "My Filters" tab, I have a list of the Web sites like the following, which I comment (by prefixing each line with `!`) and un-comment, as needed.
||reddit.com^$important
||ycombinator.com^$important
If your addiction/habit is stronger, you might need to invest that $8.
Another approach is adding them to /etc/hosts as 127.0.0.1, which makes it slightly more cumbersome to edit and also stops muscle-memory from going CTRL+T then press "N" then down arrow then enter.
No, not for me personally, I'd never.