How not to treat a customer

I went to the H/ways branch, tried on a few items, got what I wanted,plus a few other items & went to the till. On my way to the till I heard them call a cashier for the customer ahead of me (there was no cashier - seems to be the norm lately, not just at H/ways). The customer ahead of me was looking at a top left by another customer who left it while she went to the fitting room - she was going to do an exchange. The customer ahead of me & then the 1 behind me where asking the cashier about sizes available - the customer ahead of me apologized, the cashier ignored me (although she didn't ignore the woman behind me.There were other staff \floating"around but none opened up another till. When the customer came out the fitting room she grabbed the top back & said it was hers. At this stage the cashier called another staff member to come & help her with the exchange etc. It seems that the days of 1st come 1st served no longer exists & neither does customer service at your stores.I opened my account nearly 10 years ago & have watched the service go down hill & have decided that as you don't need my business I'm quite happy to close my account & go elsewhere."""