1)if bitcoin system Same in all over world why some wallet can control fees and others can’t like Blockchain.info ??
2) How wallet work with short word ??
Firstly, it is a free world and every system can decide to do whatever they like, it is only left to you as a user to know whether it is OK by you or not and make use of the one that feels okay. I do not know why some of these web wallets like blockchain, which obviously use to allow export of private keys in the past stop, but the reason is best known to them and their devs alone.