Over-55s are far less tolerant of unavailable products and web services than younger generations.
Research from SunGard Availability Services and YouGov has identified a new breed of consumers for businesses to beware of this Christmas.
Short on patience, quick to complain and happy to spread news of bad experiences, the over-55s will not tolerate it when they are unable to purchase the products they want, or use services they need.
In contrast to these "grey grumblers", the younger generation of 18-24-year-olds are far more happy-go-lucky when it comes to coping when products are not on the shelves or websites experience problems.
The research shows that when faced with an unavailable product or service, "grey grumblers" do not consider the reasons behind the problem one in two simply put it down to the company having poor customer service.
Furthermore, a similar proportion of over-55s will complain to both the provider and their friends and family, or switch providers altogether if they cannot get the product they want.
Younger people though immediately recognise when a company is experiencing technology problems and only 35% said they would complain or switch.
Overall though, UK adults are becoming increasingly unwilling to put up with poor service and availability. Faced with a service being unavailable for 24 hours (such as a website, call centre, mobile phone or email system), almost 4 in 10 (39%) respondents would look to leave that supplier.
This compares to only 24% that said they would switch provider in a similar survey in 2006.
A further one third of people (33%) would complain to the provider and tell family and friends about the problems they have encountered.
The survey questioned 2,600 UK adults.