Asking my advisor about our lab’s funding situation
The cultures differ on this point. In some countries, a PI's lab is a bit like his "private" business, or an extension of his/her house. The success of the lab fully depends on the PI's recognition, achievements, and sheer luck with the funding bodies. Naturally, PIs can be over-protective about what happens in "their kingdom", particularly if things are not going well (do they ever?)

In other places the Lab "belongs" to a University, and PI's simply inhabit it, just like postdocs, PhD students and technicians. They have some academic powers and are still responsible for finding the money to keep the place running, but the management powers are to a large extent taken away by HRs, Finance's, Senior Management, etc. It is often, but not always, lead to a better transparency, because University acts in the best interests of all employers, or at least tries to make it look like this. However, in this case PIs may not be fully aware what the situation with their funding is, particularly if University is not doing well.

In theory, as someone working in the Lab, you are a stakeholder and have all the rights to know what's going on and how long the place will run. In practice, the situation can be terribly unpredictable, and even you PI may not know what is going to happen.