With a fanny pack, you'd just move it around to your front, unless you've got belly like mine, in which case you might not fit on the ride in the first place. Or for various reasons you might not want to go on those rides, or you could have someone else in the party hold the purse/fanny pack while you go on the ride, and they you hold their "stuff" while they go on the ride. That's a common enough thing to do anyway, gun or no gun.
But this guy may not have been going on the more violent rides anyway. I didn't the last few times I went to such places (Sea World, San Antonio and Six Flags-Arlington Texas)due to being too big, and having a bad back on top of that. I still can go on some rides, and at Sea World I really go for the shows.
In a rational world, the park might provide a secure storage facility if they are going to ban or restrict concealed carry, or even if they aren't. Most of the worst incidents, such as this one, happen *outside* the gate. In the parking lot or on the way to it.
Ah, that makes sense... I’m thinking of rides more like the coasters at Cedar Point, where whatever is holding you in would not leave much room for a fanny pack. I’m the kind of person who goes to an amusement park and makes a beeline for the biggest, twistiest rollercoaster there. At that rate, I suppose you could store your weapon in a locker, but there are also armed guards all over the place if things get rough, so I’d just not bother bringing it (there at least) in the first place.