Sometimes it’s just pure obliviousness and you really need to speak up.
One of my embarrassing moments was shopping at a teacher store to supply my ex’s classroom. We were kind of enjoying the afternoon so taking our time, no big deal. Then the store people started coming over more frequently to ask if we needed help. No thank you. Eventually we make our way to the register and were shocked to discover the store closed half an hour ago. wtf, why didn’t someone kick us out, or at least stop being so damn polite and tell us they were closing since we clearly didn’t realize it? I’ll never forget the cringe of keeping people so late, and we were just enjoying leisurely shopping that could have finished long since