Well that would depend on what environment your hotspot(s) are running in, If this is in a restraunt, coffee shop, Bar ect, Then I would think it would be ok, HOWEVER if you are running as an WISP for a small town or what have you, I would say its a bad Idea. Afterall , if people are paying you for a monthly service ( think ATT, Mediacom, Comcast ) they are expecting unlimmited access and if you block update sites like that people will stop using your service if you dont allow them to do something as basic as update thier operating sysem or other software.