Anyone with any graphic editing skills at all can easily get around that problem.
They can, but if they have a lot of graphic editing skills then they wouldn't necessarily need to use the image creator.
And many people looking to use this because they don't own graphic editing software. Putting in the icons is easy in photoshop or something similar, but in MSpaint it can be time consuming.
If using Paint,
Screenshot the icon from the forum. Paste in paint.
Sample the background colour as the second colour choice.
Use the select tool and copy then paste in your card image.
On the tool options select transparency (its the bottom of the two choices for select)
You should have the icon with no superfluos colour.
20 sec an icon.