I've had the pint sized bottles for Breakfree CLP that I had for years and years. It would have the sprayer thing on it. I think I had to switch bottles once because it broke. Even had 1 gallon jug that I would pour into the smaller bottles when they ran out. I have never had it leaked on me. I'm currently using Froglube but I have 1 gallon barrels and solvent and the lube/paste. None of them leak except maybe for the paste where it might go into the thread of the cap but that's more of just having use it than something that happens and it never becomes "leaky."
I do know on the Slip 2000 bottles, they tend to have this cardboard like cap on the top. Did you remove that or punched a hole through it with the straw? If you removed it, it might explain why it is leaking. Also what sort of temp are you storing these at? Even in the garage, I don't have anything leaking so I'm not exactly sure what is going on here.