Jaw dropping customer service

I'm currently in Starbucks Gateway branch , placed my order and I'm seated far from where you collect your order as I've connected my laptop and handset devices I ask a black gentleman at the till to kindly alert the one who will be shouting for me to collect the order as I'm seated on this end the gentleman tells me they are not allowed to serve their customers I did not ask to be served but merely asked for him to alert whoever is going to be mixing my drink that I'm seated on the other end as I need to watch my valuables. what troubled me is that they refused to do this simple request but they were able to move from their workstations and have one of their colleagues recording singing happy birthday busy chasing clout on the internet instead of serving customers clearly they were hired to sing a choir instead of customer service and serving their customeers