I think I've found a faster method for this achievement using the Hoop Shot. I was able to get about 70k in about 25 minutes after a fairly quick setup. And it can probably be done faster.
Instead of putting together a bunch of contraptions that takes time/resources to set up, or just dunking 100 times on one machine for an hour and half, just use the Mat Method of placing settlement items to place multiple Hoop Shots in the same spot, with all the hoops overlapping. I put three together, started all three and used the ball to crouch dunk and get about 3k per session. You may be able to get more tickets and do the achievement faster by placing more than 3 hoop shots but 3 worked well for me.
Mat method involves placing a small rubber Mat on the ground and then placing an object you wish to clip through other objects onto it. Then you can move the mat and the object placed on it will move with it and its collision/bounding box will basically be missing, allowing you to clip objects into each other.
For quick dunking, I'd also recommend mapping the crouch button to one of the face buttons for this.
Video showing what it looks like below.
I've made another version of the video in order to better show people how to use the Rug Glitch to combine the hoopshots.