It is possible to "claim the footer" and it is not illegal, so long as
you don't take credit where credit is not due (ie, claim you made the
template).
The way to do it is to completely remove the Attribution Widget (or
Gadget, if you prefer). But how? When you go into Design --> Page
Elements, the Attribution Widget is locked so you cannot remove it
like other page elements. Well, you can unlock it. You can unlock any
locked gadget.
To unlock the Attribution Gadget, go to Design --> Edit HTML, then
search for the <footer> portion of the code. Example from one of my
blogs:
<footer>
<div class='footer-outer'>
<div class='footer-cap-top cap-top'>
<div class='cap-left'/>
<div class='cap-right'/>
</div>
<div class='fauxborder-left footer-fauxborder-left'>
<div class='fauxborder-right footer-fauxborder-right'/>
<div class='region-inner footer-inner'>
<macro:include id='footer-sections' name='sections'>
<macro:param default='2' name='num'/>
<macro:param default='footer' name='idPrefix'/>
<macro:param default='foot' name='class'/>
<macro:param default='false' name='includeBottom'/>
</macro:include>
<!-- outside of the include in order to lock Attribution widget
-->
<b:section class='foot' id='footer-3' showaddelement='no'>
<b:widget id='Attribution1' locked='true' title='' type='Attribution'/
>
</b:section>
</div>
</div>
<div class='footer-cap-bottom cap-bottom'>
<div class='cap-left'/>
<div class='cap-right'/>
</div>
</div>
</footer>
Go to the portion that says " locked='true' " and change true to
false. Save the Template. Now go to Page Elements, click Edit on the
Attribution section and then hit remove.
Voila! The entire Attribution line is now gone! But that is only the
first step.
If you really want to claim the footer, you can now enter any text you
want in that <footer> section of the code. Of course, there is no easy
to use editor, so you will have to do it in the Edit HTML portion
using CSS/HTML coding.
Note... Although this is completely legal, there is value in allowing
the template creators to get their props, but the other responses
cover that aspect.