Mac's Grab keeps opening my screenshots & dragged desktop images in Grab instead of Preview. PLEASE HELP

Ever since I upgraded to Sierra....Grab application keeps hijacking my images as the default application to open in. Which is a useless application quite frankly. I use and need the default images to open only in preview.

I've gone through all the steps that are traditionally standard. right clicked image ...click "get info" then to to "open with" ...Preview is no longer listed as a set of options in the drop down on there so i have to click "other" ...then scroll down to "Preview" and click it ....then the check box "Always open with" then click "add" ....after this I clicked on "change all" and that should supposedly do it....now all file types that are "png" should open in Preview...right? But it still doesn't. That specific file on my desktop, yes, now opens in Preview. But anytime I drag a different image off the web and onto my desktop ...if it's a PNG file it still opens in Grab.

Can someone please help me fix this.

I've also done the safe mode steps where i restart in safe mode....follow the above steps for all png and jpg images. Everything opened fine in Preview while i was in safe mode. Then when I restarted back to normal ....any dragged images from the web onto my desktop opens back up in GRAB!!

I can't be the only one having this issue. Would really appreciate if anyone can help me fix this. Thanks