Perhaps I'm not understanding what you're saying, but the small gaps between the support pillars that you seem to be showing in your screenshot ARE typically removed automatically.
Here's a quick test to show you how it works. Download this file and import it into S3D.
Then go to Supports > Generate Automatic Supports. You will see dozens of support pillars with a tiny gap between each one. If you don't make any other changes and then you click Prepare to Print, all of those gaps are removed and you see a constant pattern of support infill across the entire zone.
Can you run the same test with that same part and let us know what you see?