Tipping assistants for vendors that own the company

I've seen posts about how you don't have to tip vendors that own the company (which I pretty much agree with, unless they exceed expectations).

But how to you tip the people working for them? For instance, my DJ owns the company, but he'll have an assistant there. And the photog owns the company, but there will be a second photog and assistant too. Do I seek those people out separately and give them an envelope, or do I give the owners own large envelope with final payment and envelopes for the assistants?

I'm not sure what the etiquette is here. What do you girls think?

Personally, I tip everyone even if they are the owner of a business.

But, if youre just going to tip the assistants then I would seek them out individually just to avoid confusion with the owners.