I doubt very much that he "FONDLED" your neck. I think he may have inadvertently touched your neck as he was reaching for the tag.

Do I think the clerk behaved unprofessionally? Yes.
He obviously has a lot to learn about boundaries, personal space and comfort zones, especially if he is trying to make a sale. It's usually best not to make the customer feel uncomfortable or as if they have been violated in some way.

I just wonder at your almost homophobic attitude. If it had been a female clerk, would we be reading this letter?
Or, is it even homophobia. Perhaps you are a gay male, or perhaps the sex of the clerk was irrelevant. I don't know, as you are a perfect stranger to me.
I only have your letter.

I just think it's ridiculous to make claims like this, smudging the reputation of a clerk that you don't even know, or even dirtying the name of a business, just for the sake of a few free shirts.