Souvenir Bottles

Is there a place you can put these in the station while on the roller coasters?

Same place as everything else. The bins. Not all rides have them though. Top Thrill and Millennium require you get a locker.

I admit this was one thing Six Flags Great America has covered (drink bottle racks), that bothered me to a point. If I had the bottle it would be different I guess. But people just take their sweet time removing all their junk. Interval times would be a joke. Granted they (ride ops) also now have clocks there counting down the seconds for them.