Is it proper to cite something when using it just as an example? In academic writing, is it proper to cite something to provide it as an example of something else? For instance, we have lines like this in a number of our papers:


  Many research endeavors, including environmental and coastal hazard prediction [1], climate modeling [2], high-energy physics simulations [3,4], and genome mapping [5] generate large data volumes on a yearly basis.


Each citation is merely providing an example of a research project that generates large volumes of data (more often than not, it's not even a paper, just a URL), and content from the cited source is not otherwise used anywhere in the paper. 

I suppose I tend to think of citations as references to work whose content contributes to a significant portion of content in the paper. A citation then indicates some kind of "weighty" relation between the paper and the thing being cited. In the example I provided, it seems to me that invoking the "weighty" power of citation simply to say "yes, such a data producing project of this type does in fact exist, in case you were wondering"--and doing so five times--is somewhat excessive and that it might serve better as a footmark.

To me it seems these should either be footnotes or just be left out. In any case, it seems they should not go in the bibliography.
I am not sure about other disciplines, but this is certainly neither uncommon nor in any way frowned upon in my field (Computer Science).