It's probably meant just as a drop-off/ holding point but the workers there are lacking management. They purposefully misdirect traffic with the sign outside, they don't acknowledge you at all nor attempt to assist you to off load.
Whoever is managing this branch is failing. It's also a reflection on the company, they are not incentivizing their employees. Bad policies create bad employees. I donate to get rid of clothes I end up not wearing more than once, but if I had a choice I wouldn't donate to Goodwill.
They just profit off of people's donations. Don't be fooled by the word non-profit. Their revenue is $4 Billion this year. Non-profit just means they have to use the money they make, it's just goes to Jim Gibbons. Not sure how this retail store still holds 501(c)(3) and is exempt from certain federal taxes.