I'm actually struggling with my current company for something very similar. The marketing person I replaced had a subscription to Photoshop, but when he would create materials they would ask him to recreate them in Word 2003! he has since moved on, and I have finally convinced them to let me create materials through the cloud (through my own subscription). However, we will be negotiating my salary in a couple months after I complete my masters and I will definitely be asking for them to either pay for the subscription directly or increase my salary so I can pay for it. If a company wants quality work, they have to be willing to pay for it. Good luck, OP.

What the hell?

They should've gotten Master Suite. Of course, these days, you can't get any of those program without having to pay like $1,000 a year for them. They don't sell them in disc format anymore. It's terrible. So yeah, I see why your company wasn't too thrilled about that, OP, but they should have all programs available for their employees, and it's silly that they only have one Adobe program. Plus, who has ONLY Illustrator and not Photoshop? However, Illustrator can work very similar to Photoshop if done correctly. You can add layers, change effects, etc. It may not be exact, but it's something. Sorry they fired you, though. That was an overreaction on their part.

How is creating marketing materials anyone's dream job

or you could have just used publisher. Microsoft publisher. made specifically for marketing materials.

Gimp and Inkscape

Having been through a couple of business schools and understanding tactics asshole managers use, chances are they were trying to bully you into paying for it yourself, just to save a dime. I'm guessing your benefits package was also a bit disappointing and/or sketchy.

Most companies have an internal approval system where your boss, etc approves or declines before it goes out for purchase. They should have, politely or not, declined your request instead of firing you for it. Seriously!

You might aswell tried GIMP and Inkscape. They are free open software.