It's absolutely NOT bollux as even supposedly equivalent balls by the same manufacturer can behave quite differently depending on their exact pressure and relative perfection of manufacture.

Such things usually don't affect the short game, but as soon as you're hitting the ball hard, or more than twenty yards or so, very different things can happen even without paying attention to hitting at the valve seat or going for the zero rotation knuckle ball.

It annoys me a little that the same ball is often not used for the entirety of any given match.

Much like in the NFL (I am a Patriots season ticket holder after all!) there can easily be shenanigans involved if the home staff are sufficiently clued up - never gets reported though...