Styling of table cells, first cells in a row

I noticed that all first <td>s in a <tr> have a styling of what you would
expect a <th> would be.
This gives a problem for tables like on the bottom of this pageL
http://docs.webplatform.org/wiki/css.

I understand why this kind of styling was chosen, but maybe we should
change it because it restrictions (no headers, column headers). Another
option is adding an extra class besides wikitable.