Default [Q] How to share smartphone's wifi conncetion through hotspot.

it kinda sounds stupid but I gotta find a way to share my smartphone's wifi connection since in subway here in Korea, I get to use a free wifi but only via my smartphone since the wifi is Mac-address locked.
I found my Nexus 7 2013 to share its wifi connection with other devices through hotspot. However, my Galaxy S3 would only let me to the data conncetion not the wifi conncetion. I found this quite weird because Nexus 7's example tells me that sharing wifi connection is possible but Galaxy S3 would simply not let me to.
Is there is a way?