html element id as javascript variable

Question

Consider the following code:

Answer 1

Yes, it's been around for a very long time, which is likely the only reason it exists. Removing such a "feature" will break compatibility with existing web sites, which browser vendors are very reluctant to do.

You're correct in saying that it's not a good idea. It's a profoundly bad idea and can lead to naming conflicts as well as unnecessary pollution of the global namespace.