That’s because it makes sense when dynamically creating HTML. HTML is not a programming language, it’s simply markup - so if you want to generate some block of HTML in a loop and later access that block of HTML in JS (e.g. to interact with the UI separate from creating it in the first place), it’s a completely reasonable thing to do.
The reason I hate HTML: I’ve seen smart, reasonable people do this with IDs, and I’m not 100% sure they’re wrong.
That’s because it makes sense when dynamically creating HTML. HTML is not a programming language, it’s simply markup - so if you want to generate some block of HTML in a loop and later access that block of HTML in JS (e.g. to interact with the UI separate from creating it in the first place), it’s a completely reasonable thing to do.