> Why Deviate? > Although REST prescribes using HTTP GET, PUT, POST, and DELETE verbs for CRUD operations, some clients can’t generate the less common PUT and DELETE requests. In addition, some overzealous firewalls block PUT and POST. Thus, some RESTful APIs accept all requests via HTTP GET and place the HTTP verb in the querystring. For example, to delete user 124, the GET request would be for the following URI: /users/124?method=delete This technique is especially common in Ruby circles. Another benefit of this approach is all requests can be easily generated and manipulated in the address line of any browser.

This is a very bad idea for something like delete. It's Daily WTF material:

http://thedailywtf.com/Articles/The_Spider_of_Doom.aspx

Any firewall that blocks POST requests but not GET is a WTF in and of itself, for that matter.