(Edit: I have several Ffx addons running and no Chromium addons, so the comparison was unfair. Maybe I'll just ditch some of those addons...)
The page works fine for me, but I imagine it would suck if I had less RAM. I tried it in Chrome too and it never even got as high as 5% memory usage.
I'm willing to bet that the developers who made this page, and the managers who approved it, all have plenty of RAM in their machines.
I opened up windows task manager, and watched the mem usage for firefox.exe. Before navigating to that webpage, it was using 150 MB of memory. I went to the webpage and scrolled down as expected, and saw the mem usage peak at around 430 MB when the page first loaded, then as I scrolled down and sat at the bottom of the page, it stabilized at around 300 MB.
After closing the tab and going back to leave this comment, firefox is back to about 150 MB of mem usage. I think there is a problem with your particular installation (or add-ons or drivers), not a general problem with Firefox itself.
Memory usage jumped to about 2GB before the machine became totally unresponsive. I did something else for a few minutes while I waited for the kernel to kill anything using too much memory and get my machine back to a usable state.
While that's not a great result for Firefox, I do think the people at Nissan who did that could have shown a little more restraint.
(Mind you I have 24GB of memory on this machine. I wouldn't willingly choose to run Windows 7 on any less than 4GB.)