Joannesalfa Because C2's tilemap already does most of the same things minus these seemingly simple & common features (well, some of them). I'm not going to use an entirely different program just for a few more features..that would just negate the work Ashley has already put into the tilemap object.
Also I once used Tiled (via TMX Importer) with sprite objects acting as tiles (as Ashley and everyone else suggested) and ended up having to cancel the game because of the insanely slow preview/export/commit/update times, freezing when loading maps, difficulty managing tilesets, and tons of memory use. (It was that or re-building every single level in C2 and refactoring just about every object) You can't really load .tmx tiles into C2 tilemaps at runtime either due to the 1-tilemap-per-object design. That said, I strongly advise devs to NOT use Tiled with C2.