I haven't worked with any of the template toolkits, but I imagine that the HTML oriented toolkits might implement automagic HTML entity quoting, which would get in the way or at least be inconvenient. Also, such toolkits might expect to be able to parse their templates with HTML::Parser, or expect their templates to be valid XML / XHTML, except for their own special tags. Some toolkits even bear HTML in their name, which suggests that they cater specifically to HTML output (HTML::Template and HTML::Mason).
But as I said, I didn't work with any of the toolkits, so this remains to be evaluated by the actual user.
perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ; # The
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' # web
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