Without pics or better descriptions of these "annoying" plastic boxes it's not possible to comment on situation. I have seen videos of some "expert" preparing a 4x4x6 in. or craft box as a "vivarium" for a frog and that is very wrong.

At the same time, there are professional built rack systems for some reptiles/amphibians (i.e. Vision Products – Racks) and there is nothing wrong with them. As a matter of fact I'm currently saving money for a small one... and no offense taken !