KISS principle on the web

How do you think, how justified is the creation of commercial websites (offering offline services) consisting of a minimum (ideally one) pages on the web?

My friends provide services for conducting fiery and light shows (well, everyone saw the fire show, probably). When we designed a website for them, we came to the conclusion that all the information that would interest a client can be placed on one page in general.
Thus, in a couple of hours, a site appeared from a single page, where you can find answers to all the questions that might interest potential customers.

How do you think, how reasonable is such a desire to simplify everything and how much did we manage to do it? How would you react when ordering some kind of service if the artist's site met you with one page? What information do you lack if you ordered something?
In short, you need feedback about the idea itself (well, and about the result, it won't be superfluous either, of course).
')
what we did - fireshowkazan.ru

UPD
habrahabr.ru/blogs/ui_design_and_usability/37396
here, by the way, there was also a post on the topic.