I was in your situation seven months ago. I openly told them that I am not the type who'll go for commitment, and they were ok with that for some time. After a while, one of them dropped out because it "seemed immoral and wrong", and the other one was so good to me that she became my girlfriend and stayed my girlfriend to this day.
If you plan to use them just for bangs, tell them in a subtle way that they can't expect commitment from you. Even in my country (slavic "patriarchal" traditional country) girls like that are starting to become rare because of influx of facebook, western media etc. so you should show them that men value those traits.
The oint is, if you hurt them you risk creating two more bitter shitty feminists.
If you plan to use them just for bangs, tell them in a subtle way that they can't expect commitment from you. Even in my country (slavic "patriarchal" traditional country) girls like that are starting to become rare because of influx of facebook, western media etc. so you should show them that men value those traits.
The oint is, if you hurt them you risk creating two more bitter shitty feminists.