To address this:

> Why aren't questions like these just deleted instead of being closed?

They are, actually deleted - but after some time has passed. That "time" varies from a week to a month to couple of months, but I do spring cleaning every now and then, and I know for a fact that few high rep users put in their delete votes.( 10k+ users can check existing deletion votes from [here](http://superuser.com/tools?s=1&tab=delete&daterange=last14days), or the [link](http://www.google.com/search?q=%22closed%20as%20off%20topic%20by%22%20OR%20%22closed%20as%20not%20constructive%20by%22%20OR%20%22closed%20as%20not%20a%20real%20question%20by%22%20OR%20%22closed%20as%20too%20localized%20by%22%20inurl:superuser.com/questions%20site:superuser.com%20-site:%2A.superuser.com) that Dennis [provides](http://meta.superuser.com/questions/5495/why-arent-more-questions-deleted#comment14325_5496)

We don't do insta-deletes, except in cases where it's blatant spam or egregiously off topic - the intention is to provide the OP/community the option to revise the post so that it's acceptable.