Paying for things from your own pocket

I had a conversation with my husband recently about finances. I had just returned from the ECOO conference (which I paid for myself), where I had purchased a $100 LiveScribe pen (which I paid for myself) and I wanted help to set up a PayPal account so I could buy several Minecraft video game accounts to use them for a club at my school (which I was planning to pay for myself). My husband was, understandably, concerned.

"Why do you have to use our money to buy all these things for school?" he asked.

This isn't just a recent phenomenon either. The last pair of picture books I've read with the primary classes as part of their library lessons (Goldie Socks and the Three Libearians and Bats at the Library) were books from my own personal collection that I bought with my own money. Why do I spend my own hard-earned cash on school items? It's not like I have oodles of extra money begging to be used.
I came up with a few reasons.

1. I have control over things when I own them outright. I don't have to worry that the book I want to use for a particular lesson has been borrowed by a student when it's MY book. 
2. I don't have to worry about obtaining permission, begging for funds or providing a scripted budget proposal that may get shot down. When I had my Tamagotchi Club years ago, seven of the gadgets were mine - it was an experimental club that might have been denied funds if it relied on school money to start. School boards must be accountable for their purchases and certain expenses might be seen as a waste of taxpayer funds - it's easier just to buy it myself.
3. If I believe in a project, I'm willing to put my money where my mouth is, even if it's my own money. Aviva Dunsiger, a grade 1-2 teacher, bought two iPads for her students to use in class because she was convinced that this would help her students learn, and she's had great success with these tools. Yes, this may mean that her students have more technology available to them than other classes, but it is important to Aviva and how she runs her class.
4. I don't want to insist that students pay for things because they may not have the money at home to do it. The Ontario Ministry of Education recently came out with some guidelines on charging fees for required class elements and to sum it up quickly, schools can't expect kids to pay extra for things they need for their regular lessons to be successful. 

All these justifications still don't excuse the fact that I pay for a lot of my professional development and classroom essentials using my own money. I have solicited funds from different organizations to help defray costs, but that is a huge undertaking of time to complete forms and explain rationale. For example, if it weren't for my mother's financial assistance, I never would have been able to attend the IASL conference in Jamaica this past August. I really do need to figure out another way to fund some of my little projects but in the meantime, I'll keep spending my pay cheque on books, conference registrations, and technology.