Do you lose any friendship points if somebody sees you digging in a garbage bin?

When villagers are too close to you while you're "using" a trash can, they are usually disgusted and say something about it. But does it have any negative effect on friendship?

A bit of a late update, but I saw this in-game message on TV:

Pulling out the trusty decompiler, here's how checking the trash works:

• It only affects an NPC within 7 tiles of you.
  • ...unless that NPC is Linus; he doesn't care if you dig in the trash.
• The NPC will give one of three disgusted responses.
• You lose 25 friendship points (10% of a heart level) with that NPC.
• You may get a random item. (It appears that better luck that day gives you a better item.)

Yes, whenever you see the grumbling speech bubble, it means the villager lost some of its friendship with you. This can happen when they see you rummaging through trash bins, when you hit them with a stone fired from a slingshot, and when your spouse finds a slime inside your house.