There’s at least a couple of puns going on here. You may already know some of the following.
First of all, Perl is a programming language that has been around since the late '80s. It was designed as a system administrating, text processing glue language with aspects of shell scripting, awk, sed, the greps and a whole host of other things.
This is the first part of one of the puns. Perl was, and may still be, used as a filter in command line pipelines.
The other pun comes from the fact that perhaps the most important Perl book, Programming Perl was published by O’Reilly who generally put some sort of apparently unrelated animal on the cover of their titles. For Perl this was a camel.
Camel is, or was, a brand of cigarettes. Therefore this is the second pun. The pack of cigarettes has “Perl” where it should read “Camel” but still has the picture of a Camel, like both the book and the cigarettes.
Cigarattes, of course, often have filters on the mouth end of them, which completes the first pun. I do not know if any Camel cigarettes have these, but that’s not strictly important. Some cigarettes do. Perl-branded Camels almost certainly would do.
The third (fourth?) pun, which may or may not be intended, is that some people think that programming in Perl is damaging to one’s health.



I dunno. There are some of us who run Mint not because we don’t know what we’re doing but because we do* and we don’t want to have to deal with any more nonsense than we absolutely have to.
From that small cohort, there are those of us who’ll frown when all we have open is a few browser tabs and the system’s using 8GB of RAM, twice the “recommended” spec. On startup with nothing running it’s over 1GB.
It’s hard not to see it as wasteful when you’re old enough to remember perfectly good machines running on single-digit megabytes. **
* Or at least, think we do.
** Yes, things are much more complex these days. But are they really a thousand times more complex?