On Unauthorized Copies of Software
Many call the use or distribution of unauthorized copies of software “piracy”, but I still don't get what it has to do with boarding ships, so I won't call it that.
If you know where to look, you can find unauthorized copies of many different programs, and the reason is very simple: those programs are always commercial, and the unauthorized copies are always gratis, it's obvious why someone would want to use that over an authorized copy, and it definitely has a “stick it to the man” charm to it. You won't find unauthorized copies of non-commercial software as easily because there's no financial incentive, and there's almost no point in making unauthorized copies of commercial libre software because redistributing it for no cost is permitted under the terms of the license, therefore most would rather distribute a gratis copy authorized under the terms of the license. Because of this, I'm talking specifically of unauthorized copies of commercial proprietary software whose primary purpose is to use said software for no monetary cost.
While unauthorized copies are definitely alluring, resorting to them is a bad idea; not because it's illegal in most countries: I couldn't care less, not because some consider it immoral: I don't believe in copyright in the first place, not because you “should support the author”: if Adobe went bankrupt tomorrow I'd throw a party, if anything, because I hate DRMs, I should joy at seeing them defeated one after another, but, in reality, resorting to unauthorized copies you're just doing a disservice to yourself.
The first issue is that it's sending the wrong message: even if you've got a copy for no cost, that proprietary software is still proprietary, so the message you're sending is that's you're fine with using proprietary software as long as it's non-commercial (or at least freemium), which, in turn, justifies the existence of behemoths of evil such as PayPal and Google. Gratis or not, the problem with proprietary software is that it's proprietary, there's virtually no difference between paying to use a proprietary software and using it for no cost, meanwhile, all software has the right to be commercial, including libre software.
The second issue is that if the software you installed was malware in the first place (which is almost always the case with proprietary software, and even when it's not, it's extremely hard to verify it's indeed not malware), it doesn't become any less malware just because you've got it for no cost. The software is phoning home whether you've paid for it or not, it's shoving ads at your face whether you've paid for it or not, and you can't modify it even if you've already breached the license because you have no access to the source code.
The third and last issue is that you're making yourself dependent on that software, in other words you're playing the enemy's game. Companies that make proprietary software give outrageous deals to schools and universities to make sure they raise the children and young into users that are absolutely dependent on their software, with the goal of getting a major gain later on. From the perspective of Matlab, what's the difference between a university getting a huge bulk of licenses for essentially no cost, and you using an unlicensed copy of Matlab? None. You still become dependent on Matlab, which makes the entire industry more dependent on Matlab, which allows Matlab to get away with more and more abuse. Proprietary software is bad if it takes over one person's computer, so, the last thing you want is to enable it to take over an entire industry. In other words, despite their claims, and the hordes of useful idiots roaring at you that what you're doing is illegal that's your duty as a user to give up your money to be abused because being abused for free isn't enough, you're actually doing them a favor.
So, legally obtained license or not, it's better to avoid using proprietary software as much as possible. Whenever you have a job to get done, rather than jumping directly to the most popular “professional” proprietary software and getting a copy of it, authorized or otherwise, you should always try a libre program that fits the same niche.
That method is not perfect, for example, if you get passed a PhotoShop file, there's little you can do but open it in PhotoShop, because it's an undocumented proprietary format, and like a significant amount of proprietary formats, the support for it in completely libre programs exclusively comes from reverse engineering and it's lackluster best. In that case, can you ask to receive the file in a format more compatible with free software tools? There are a few things you can try before jumping to the proprietary tool, but, sometimes, unfortunately, there is simply no way around it, if that ever happens, how important it is to open that exact file? The choice is between not getting something done and using a proprietary program, hardly an easy one, but, in the case of the latter, I see no moral issue with using an unlicensed copy to avoid to directly finance the development of a proprietary program.