" a bid to boost their customer services"
More like reduce them.
Anyone with a forced smile basically starts to look like a psycho - yeah, that'll bring the customers in.
Or a punter with some bad news story being met with the company-standard gormless grin as opposed to some genuine empathy will also feel like taking business elsewhere.
Or a customer with a complaint will get well and truly pissed off if the staff member keeps up the inane grin all through the proceedings.