You could create that via pure HTML/CSS, and I see no reason to do so otherwise. I can tell you from the client that it's highly likely that no databases were involved. Uploading images with PHP and storing to SQL isn't really an issue, although it's a good deal of work. Bottom line is, ify ou want to do it, you can. The client will benefit from your work if you do it.
It also allows dynamics. If your client had an image needed to be uploaded, he'lln eed to contact you. But if you automate it with an upload form, and use a loop to print out each result, he won't need you.
Sounds like from your needs, you'll need the upload form. If you have a fixed set of images from the get go, and you don't really see it changing (often or otherwise), you can just stay static.
Heh, interesting you linked that page. I coded the homepage