Political Activism
If the reason you get is "no budget", then you may have to advocate for us to be able to increase our available monies before we can continue on the path to being open-source. Here's a secret about library funding: it's really hard to get. In Washington State, where I'm headquartered, if the library wants to pass any issues regarding raising bond money or trying to take advantage of a good economy to raise more money and deliver more services, the library first has to get 40% of the people who turned out to the last general election to vote on the issue, regardless of whether they say yes or no. If the library manages that, then the library has to convince 60% of the total people who have voted on the issue that they want to pony up the additional tax money. So the library not only has to motivate enough people to get out and vote, we then have to convince a supermajority of those who do vote to approve more funding for us. Let's put it this way – it's already hard enough for the library to convince people to keep them funded. Even more so in an environment where a significant number of people believe all taxes are evil and should be abolished, regardless of what services or benefits they generate. A public library has a vested interest in not generating additional heat against them. In some unfortunate cases, that may be a greater motivator for a public library to change than the desire for the library to be an institution that truly reflects its community.
Expect more from your public library, and they will try their hardest to meet your raised expectations. Otherwise, they're screwed, and they know it. (Or they should, anyway.)