work at or work for

[chum]

I once worked at Starbucks...

I once worked for Starbucks!

Are both grammatically correct?

Thanks!

[englishstudent]

They are both correct. The difference in my mind is
that in #1, I may not be necessarily employed by Starbucks.
That is, I might be an employee of a contractor/sub-contractor
and have been deployed at Starbucks, whereas in #2,
I am employed by Starbucks.

Let us wait for the experts.

[chum]

ok...let's see what the experts will say...thanks anyway for your answer...^^