Boy and Acorn - thanks for the replies but I really don't understand - I've done a number or sites using a hamburger menu made up of rectangles and they are completely sharp!.
I've also designed lots of other "shape" graphics and once again I don't get it - they're sharp when published.

I need to repeat what I said though - the Instagram icon is made up of 3 shapes with no grouping/soft grouping but it's blurred.
Also that cell phone pic - it's crazy blurred but it's a 539dpi image in XDPX!

Please check www.mikekaplan.art again - I've added the B "logo" which is a shape plus a rectangle made with the rectangle tool, and then converted it to an editable shape - when published, the "B" is blurred and rectangle sharp!!