Battery box

Can someone please explain to me just why some plastic battery boxes are in excess of $300?
Is it just because they're sold as a 'battery box' for folks using solar, and they have a couple of holes punched in them already?
What's the difference in these? Corrosion resistance?

http://www.wholesalesolar.com/9941556/radiant-solar-technology/battery-enclosures-amp-boxes/radiant-solar-technology-hdpe-battery-enclosure-for-4-t105s-no-drain

http://www.lowes.com/pd_306966-61896-306966___?productId=4487914&pl=1&Ntt=18+gal+tote

Looks like a lot of work goes into those $300 boxes. They do look nice. I'll take the $20 plywood box .