Older people use it is because they don't want to change or learn something new. Especially in a company already entrenched in Perl development, their is little benefit to switching to a better language compared to the cost of forcing people to learn a whole new technology stack when they are more than content with Perl. However, new companies are much more free to build on whatever technology stack is most appropriate.
I've also noticed over time that lots of non-CS majors can and do program in scripting languages because they are relatively easy to pick up and get things done with. These people are usually more aligned with an IT career in that scripting constitutes only a fraction of their job. If they happen to learn Perl and PHP first, then that is what they stick with.
These people may like to program, but it is not the favorite part of their job and they have other work activities they enjoy more. More importantly, they know little to nothing about software design principles and are not interested in improving their software development skills. They would rather spend their time learning about something else that interests them more. Therefore, they don't even know how to appreciate the advantages more modern scripting languages offer. To these people, languages like Perl are more than sufficient to get their job done, and they are probably right.
However, as people who know better, I believe we should be encouraging better languages in a friendly way whenever possible. When my IT friends ask me about any questions related to programming, I usually try to point them to Python or Ruby for a solution. If they are asking questions they are probably interested in learning something new!
edit: changed wording based on reply from gamache.
I disagree with your implication that Perl is suitable for newbs but should be discarded for "better languages" by people who are interested in learning.
In fact I would invert your statement: I think Perl is not a good choice for people without good programming habits, but for those who know how to use it, it offers more power of expression than most of its peers.
(Also, datum: count me in as an "older person" preferring Perl for most tasks despite knowing Ruby, Python, JS and half a dozen other languages.)
I never meant to imply that Perl is suitable for newbs, but rather most scripting languages are. I would much rather newbs learn another language, in fact. I changed my wording in my original post to reflect that.
Also, for my background, I learned Perl as my first scripting language and after writing a ~1k line code project in it, decided that for anything over 200 lines I would rather use Java. Later when I learned Python I was vindicated in that almost everything I instinctively disliked about Perl was absent in Python. Since then I have learned many other languages as well, and I also know Perl the language better than most of my co-workers
I actually tend to find the opposite: I know lots of CS majors who love perl and C, and lots of web-design-focused non-cs-majors who love ruby, python, and php. Both groups are approx the same age (late-20s/early-30s).
I've also noticed over time that lots of non-CS majors can and do program in scripting languages because they are relatively easy to pick up and get things done with. These people are usually more aligned with an IT career in that scripting constitutes only a fraction of their job. If they happen to learn Perl and PHP first, then that is what they stick with.
These people may like to program, but it is not the favorite part of their job and they have other work activities they enjoy more. More importantly, they know little to nothing about software design principles and are not interested in improving their software development skills. They would rather spend their time learning about something else that interests them more. Therefore, they don't even know how to appreciate the advantages more modern scripting languages offer. To these people, languages like Perl are more than sufficient to get their job done, and they are probably right.
However, as people who know better, I believe we should be encouraging better languages in a friendly way whenever possible. When my IT friends ask me about any questions related to programming, I usually try to point them to Python or Ruby for a solution. If they are asking questions they are probably interested in learning something new!
edit: changed wording based on reply from gamache.