Autocreation of a .htaccess file in data folder?

When I uploaded the folder, there wasn't any .htaccess file.
But, when I run the sitemap generator through Scheduled Task, the sitemaps were created along with a .htaccess file which has "deny from all" as it's content.

So, is it supposed to be created automatically? How it effects the sitemap crawling by spiders?

Sorry if I am being too aggessive, but I am seeing a huge drop in indexed URLs. It was about 105,000 pages last month and now is just 15,800 as on today.

Thanks
ipnet

This file stops DIRECT viewing via vbseo_sitemap/data/sitemap_x.xml.gz
It should be accessed via /sitemap_X.xml.gz only.

So, there's no need to worry about that.. right?

Right, this is the default/correct case.

Thanks..