The Magic Armor wasn't a rip-off in my opinion. Sure it costs 598 rupees, and steals your Rupees every second you have it equipped, but the Magic Armor gave a good use for Rupees. The 3D Zelda games had an over abundance of Rupees, and Twilight Princess is no exception to that. Rupees were hardly used, as you could find perishables by defeating enemies and cutting grass.
Other than the Magic Armor, Rupees are only used to get bombs, one Piece of Heart, fix a bridge, and get Malo Mart in Castle Town. Even after all of that, you'll still get plenty of Rupees as you traverse the other several dungeons. Not to mention, if you want to 100% the game, you have to find all the Golden Bugs and give them to Agitha, which means even more useless Rupees.
At least with the Magic Armor, you were able to put Rupees to good use. Not to mention, that if you need to empty your wallet a bit to get a Rupee in a chest, you could always just equip it for some time until the Rupee you want will fit into your wallet.