The last several years I haven't played enough to have a home course. I actually like to play different courses. When I do play, it's usually been out of town trips, so I play various courses.
My club has two courses. One designed in the 1920s so it tops out at 6345 yards but has tight fairways and small greens. It is a real test of accuracy and knowing your game. The second course was built in the late 70s/early 80s and tops out at about 7200. It hosted a PGA Tour event for several years back in the 80s. It is long with more generous fairways and greens but has lots of water to be penal.
I spend most of my time on these two courses with the majority on the longer course because it is closer to my house.
We have a daily fee course in town that is owned by Charles Coody, 1971 Masters champion. It is always in great shape and has some really outstanding holes on it. I can be pricey and at times hard to get on. I play it about two or three times a year.
The fourth option in town for me is the Air Force base course. It is never in great shape, but the greens are usually good. The layout is fairly vanilla with a few neat holes. You could easily play without a driver. Since I work on the base, I end up playing here quite a bit. During the cooler weather, a quick 9 during a long lunch makes the day go by much better.
After much blathering, the answer to the original question is about 65-70% of my play occurs at my home course.
I (we) don't have a membership anywhere so don't really have a home course. Plus there is a lot of golf options close by and we like to mix it up. First of, memberships for the most part of out of our price range. Secondly, we are basically weekend golfers.
One day we (my wife and I) might consider joining a league or maybe do one of the frequent player offers they have which are like the one course near me offers:$425 for 20 rounds of 18 (walking), then each round of 18 after the 20 is only $21.25 (walking). I guess that is a mini membership in a way.
Generally though, we like to change the local courses we play, especially if there are deals!
I work at a golf course, play most of my rounds here. It is host to many tournaments so it is a good test. At times I will switch things up and play other courses. But really like the track here. Suits my game very well.
I like playing different courses I think it makes me pay attention an play the layout instead of just playing same shots. I like my home course but I get lazy an don't always play it the smartest. On a different course I pay more attention an try to play the right shot.