Dollarama review: customer service

My wife went to return a defective stool chair with 3 year old (he was carrying his small bike), being a new immigrant she was nervous and was being told aggressively that they are not responsible for the bike, for which she said ok and she will be quick. However when she checking the exchange product one of the cash rep. yelled again to be quick making her feel guilt ridden as if she did something wrong, meanwhile when she yell everyone was watching her. Due to this mental harassment she starts crying and came back without any exchange. This whole scenario could be avoided with good customer service and friendly behaviour.
Now we decided to never do shopping from Dollarama. Hope in future customers don't have to suffer like this.