Just wanted to chime in since I thought I might add a different perspective.
I work in documentary and unscripted TV full time. This includes nature, wildlife, action sports, human interest stories, and hosted programs. Almost always on-location.
To be blunt, if I didn't own a camera package, I wouldn't get hired.
The nature of doc and unscripted TV tends to be quite last minute. Just this morning a producer from a major network asked if I could fly out in 2 days for a 4-day doc-style shoot, everything shot on location (i.e. out of the back of a rental SUV). This happens all the time, and only if I'm lucky will I have work booked more than 2-3 weeks in advance. Not my preference, that's just the industry trend.
So, this necessitates a ready-to-go-at-all-times mentality and equipment package. There simply isn't time to rent. Often times I am flying into some far-flung little city, because that's where the story is, and I need to have a reliable way of getting the gear there quickly and efficiently; no time to deal with a truck full of pelican cases. But in addition, my shoots can get stacked back to back, so the thought of making runs to the rental house before and after each shoot doesn't represent a good use of my time and energy.
Regarding the financials, I simply include the gear rental rate in my day rate. If they need interviews, I have an additional lighting and grip rental rate. Sometimes the production company wants to use their own gear, so I have a rate for that too. But in my experience, 9 times out of 10, they know that paying my rental fees and going "all in" will save everyone time and effort. No dealing with rental houses, no prep days, no extra insurance to manage, no equipment surprises, etc. And, sorry if this sounds cheesy, but there is something to be said for letting an artist use their own tools.
Regarding actual cameras...the discussion these days isn't so much "what's your camera package?" It's more like "Do you have the FS7 or C300?" Again, totally subjective, but those are the 2 cameras that get the most requests. Simple and reliable workhorses, and they produce excellent results. If your answer is "no" then you're probably not getting hired. Doesn't matter if you own a "better" camera; they want the same camera they used last time. Or, they want the same camera the b-cam guy is operating, which is also usually an FS7 or C300.
Of course you also need a lighting package, and increasingly a need to know how to run audio, but that's a different story...