Both photos clearly have the contents (in oz/gr) on them, and they appear perfectly standardized amounts. I don't think there's any conspiracy going on here. As to the conditioner, I quite like the trend of having multiple sizes of things (e.g. for travelling) and I'd hate the branding to be different depending on an implementation detail like the amount of product I'm buying.
I mean, you can see conspiracies everywhere if you look for them, but the examples you're showing don't convince me in the least.