You know those blackberries you just picked? There are worms in them. Tiny white worms, almost transparent, that will ultimately blossom into fruit flies.
If you ever bring fresh fruit home and notice a few fruit flies in your house, guess where those came from...
Also, having grown up on an apple farm, I can tell you for sure, washing fruit as soon as you bring it home strips off the fine coating of natural wax and makes the fruit spoil more quickly. Its fine to wash just before you eat it, but washing it out of pure OCD is a good way to spoil fresh fruit.
When I get my fruit from our CSA home, I only rinse food that's visibly dirty, usually melons. Because they'd make a mess everywhere. Everything gets stored and washed at dinner time.
As I always told my kids when it came to eating mulberries, give them a quick once over, then enjoy. Because you don't want to get a good look at them.