I carry what I feel comfortable with for that day. I don't hunt as much as I used to, but I carry every day. Some days an extra mag, some days not.
In the old days when I was a L.E. tracker, and worked at locating marijuana growers on the Okie-Texas border river bottoms, if I carried an AR, I might carry 6 to 8, 30 round mags. If I carried "ole reliable", my life long friend, a now 54 year old Model 94 Winchester 3030, I would carry about 20 extra rounds, and 8 in the rifle.
I never thought much about it then, but lookin back it seems kinda odd, doesn't it. I guess regardless of what your huntin, it's about comfort, even when you don't think about it.