Square brackets in HTML form arrays. Just conventional or with a meaning?

Question

I frequently see, in particular in the PHP world, the following writing if you want to create a FORM array.

Answer 1

They address a limitation of PHP, which doesn't generate an array automatically if multiple values with the same name are submitted, for example from a set of checkboxes or a multiple select. (IIRC it only returns the last value.)

Personally I've always thought it to be a pretty shoddy workaround. Even Classic ASP could cope with that without requiring client-side additions to markup. The server-side platform has no business imposing markup requirements on the client in this way.