Weeding out Preview Textures with LoadAllAssetsAtPath()

Code (csharp):

1.     static ArrayList GatherAssetsRecursivelyAtPath(string folderPath, Type theType, ArrayList list) {
2.         string[] files = Directory.GetFiles(folderPath);
3.        
4.         foreach (string file in files) {
5.             UnityEngine.Object[] objs = AssetDatabase.LoadAllAssetsAtPath(file);
6.             foreach (UnityEngine.Object obj in objs) {
7.                 if (obj.GetType() == theType) {
8.                     if (obj.GetType() != typeof(Texture2D) || (obj.GetType() == typeof(Texture2D)  obj.name != "Preview Texture")) // Isn't there a better way to do this?     
9.                         list.Add(obj);
10.                 }
11.             }
12.         }
13.        
14.         foreach (string directory in Directory.GetDirectories(folderPath)) {
15.             GatherAssetsRecursivelyAtPath(directory, theType, list);
16.         }
17.        
18.         return list;
19.     }
20.  

When I load up all Texture2D at a path, I get the preview textures along with it. That'd be all fine and good if I wanted them, but in this case I don't. Is there a non-hacky way to skip them?

The specific line I'm referring to is the one commented "Isn't there a better way to do this?"

Thanks,
-Jon