Laravel 5.1 Middleware caching doesn't catch Route-Model bindings - php

Question

I've got a middleware setup that's caching the HTML output of each public Controller request, in each of my controllers' __construct method.
public function __construct() {
$this->middleware('auth', ['except' => ['index', 'show']]);
$this->middleware('cache.get', ['only' => 'show']);
$this->middleware('cache.put', ['only' => 'show']);
}
The caching is working great, as expected, except for one thing: I've got Route-Model bindings setup in RouteServiceProvider.php for easy accessiblity of models in their respective controllers, like
public function boot(Router $router)
{
parent::boot($router);
$router->bind('posts', function($id) {
return \App\Article::findBySlugOrIdOrFail($id);
});
$router->bind('tags', function($name) {
return \App\Tag::where('name', $name)->firstOrFail();
});
$router->bind('artists', function($slug) {
return \App\Artist::findBySlugOrIdOrFail($slug);
});
Basically what's happening is even when pages are cached, I'm still getting a single query for each route where it's looking up that slug (SluggableInterface) or id. Wondering if there's a way to do this where the query doesn't occur when a route is cached? Or is that just not possible?
Thanks!
EDIT
Here's my caching middleware:
class GetCache
{
/**
* Handle an incoming request.
*
* #param \Illuminate\Http\Request $request
* #param \Closure $next
* #return mixed
*/
public function handle($request, Closure $next)
{
$key = StringHelper::keygen($request->path());
if (Cache::has($key) && Auth::guest()) {
$content=Cache::get($key);
return response($content);
}
return $next($request);
}
}
class PutCache
{
/**
* Handle an incoming request.
*
* #param \Illuminate\Http\Request $request
* #param \Closure $next
* #return mixed
*/
public function handle($request, Closure $next)
{
$response = $next($request);
$key = StringHelper::keygen($request->path());
if (! Cache::has($key) && Auth::guest()) {
Cache::put($key, $response->getContent(), 600);
}
return $next($request);
}
}