I've never had an experience like that at a department store yet, but we only have a Nordstrom where I live and I've never had a bad experience with them.
However, I was at a local RC Willey's a few years ago (furniture store) with my dad buying some speakers for his new desktop. This persistent SA kept bugging us, I told him a bunch of times that I didn't need his help. Every time I pick up something, he'll come running over telling me about all the specs of it. It got to the point where I told him I know how to read. I finally decided on some Bose speakers, picked those up, and he came over and gave me a post-it of his employee number. He said to give this to the check out person, "and make sure to tell them I helped you." I held on to his associate number, so I can complain at the cash register about how rude he was, and then I called and spoke to his manager. I've never been so upset at an SA before.
However, I was at a local RC Willey's a few years ago (furniture store) with my dad buying some speakers for his new desktop. This persistent SA kept bugging us, I told him a bunch of times that I didn't need his help. Every time I pick up something, he'll come running over telling me about all the specs of it. It got to the point where I told him I know how to read. I finally decided on some Bose speakers, picked those up, and he came over and gave me a post-it of his employee number. He said to give this to the check out person, "and make sure to tell them I helped you." I held on to his associate number, so I can complain at the cash register about how rude he was, and then I called and spoke to his manager. I've never been so upset at an SA before.