If using spray bottles, they should be filled with demineralized water. Tap water contains minerals which could damage the leather or leave stains. I would therefore not recommend the bathroom shower.
On the other hand, people machine wash their jackets using tap water.
@Carlos840 you use spray bottles right? Do you use tap water.
I do use spray bottles if i don't have acces to rain.
When i lived in London i used demineralized water as London water is super hard and would leave a white deposit on black leather.
Now that i am back in Belgium i use tap water as i have a water softener.