I think I can suggest some other options that will make your underlying problem more clear which is that it's supposed to be html, but there is no content (content-length = 0).
More concretely, this
wget -S -O export_classement.html 'http://pro.allocine.fr/film/export_classement.html?typeaffichage=2&lsttype=1001&lsttypeperiode=3002&typedonnees=visites&cfilm=&datefiltre='
produces this
Resolving pro.allocine.fr... 62.39.143.50
Connecting to pro.allocine.fr|62.39.143.50|:80... connected.
HTTP request sent, awaiting response...
HTTP/1.1 200 OK
Server: nginx
Date: Fri, 28 Mar 2014 09:54:44 GMT
Content-Type: text/html; Charset=iso-8859-1
Connection: close
X-ServerName: WEBNX2
akamainocache: no-store
Content-Length: 0
Cache-control: private
X-KompressorName: kompressor7
Length: 0 [text/html]
2014-03-28 05:54:52 (0.00 B/s) - ‘export_classement.html’ saved [0/0]
Additionally the server is tailoring it's output based on how the browser identifies itself. using wget does have an option to include an arbitrary user-agent in the headers. Here's an example what happens when you make wget identify itself as Chrome. Here's a list of other possibiities.
wget -S --user-agent="Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.152 Safari/537.36" 'http://pro.allocine.fr/film/export_classement.html?typeaffichage=2&lsttype=1001&lsttypeperiode=3002&typedonnees=visites&cfilm=&datefiltre='
Now the output changes to export.csv, with type "application/octet-stream" instead of "text/html"
HTTP request sent, awaiting response...
HTTP/1.1 200 OK
Server: nginx
Date: Fri, 28 Mar 2014 10:34:09 GMT
Content-Type: application/octet-stream; Charset=iso-8859-1
Transfer-Encoding: chunked
Connection: close
X-ServerName: WEBNX2
Edge-Control: no-store
Last-Modified: Fri, 28 Mar 2014 10:34:17 GMT
Content-Disposition: attachment; filename=export.csv