Is turning input and label into block level items okey?

Is turning input and label into block level items okey?

I know that you can't (semantically) do something like:
<p>
<div> Lorem... </div>
</p>
I am working on the comment_form() for WordPress:
<form...>
<div<
<label>Label<label><input...>
</div>
...
</form>
I am using Foundation's mixin's (sass) to set a grid to label and input.
This mixin will make the label and input a block (those are normally a
inline). Is this, okey? Should I put the label and input in 2 different
div's again and set the grid mixins on those instead?
What I also found in the default comment_form() function is:
<p class="form-submit">
<input name="submit" type="submit" id="<?php echo esc_attr(
$args['id_submit'] ); ?>" value="<?php echo esc_attr(
$args['label_submit'] ); ?>" />
<?php comment_id_fields( $post_id ); ?>
</p>
Because I can't change that p to a div I probably have to recreate the
hole function. I think I need to do this because Foundation will set the
display to block for the input submit. Should I leave it as is or if I
want semantic markup, should I recreate the function?