It's not weird or gross.
Frankly it's none of your business!! But if you think of it like a roller coaster ride, with the moment before you descend being the peak of orgasm, it can help.
This is likely the result of deep cultural biases that many of us hold unconsciously.
The energy stimulation expelled during masturbation impacts both mental and physical behavior.
If you make genital stimulation into a big deal, you could end up reinforcing the behavior and actually see more of it.