As a hobby, photography is not exactly cheap. It's also not outrageously expensive when compared to a lot of other leisure activities... Like collecting classic cars as one over the top example. The reality is that photography costs whatever you can afford to spend.
Long term, for a lot of people, shooting film is likely to cost more than shooting digital. The differential might not be as big as you would assume though.
A good quality digital body is going to set you back several thousand dollars and they date quickly. At some point that expensive camera body is going to be worthless junk and probably end up in landfill. A lot of the photographers I know probably upgrade their camera every few years, losing 30-40% of the purchase price every time. Lenses hold their value much better than bodies but still depreciate over time. It also seems that a lot of digital shooters own a lens for every occasion, it's a big investment.
Film cameras and lenses, on the other hand, increase in value over time. Much of the equipment we use is no longer made and used gear is the only option. Most of my kit would have increased in value by 100-250% over the time that I have owned it. Good for me, not so good for someone starting out though.
The real difference is the cost of film and processing. Every time you press the shutter button it costs money. The larger the format, the more expensive it is to shoot.
Here are a few examples (approximate prices) of a couple of popular film choices. Other films may be significantly cheaper or more expensive. You can often buy cheaper by buying in bulk:
35mm Ilford HP5: $12.50/roll
35mm Kodak Ektar 100: $17.00/roll
120 Ilford HP5: $11.00/roll
120 Kodak Ektar 100: $13.20/roll
4x5 Ilford HP5: $70.00/25 sheets
4x5 Kodak Ektar 100: $80.00/10 sheets
8x10 Ilford HP5: $275.00/25 sheets
8x10 Kodak Portra 160: $380.00/10 sheets
If you send your film off to a lab there is an additional cost for developing and scanning. The cost to develop a roll of colour film and a high resolution scan of each image is around $20.00 and around $30.00 for black and white film.
Developing film at home is not difficult to learn and costs very little compared to paying a lab. A C-41 colour developing kit costs about $60.00 and will process around 20 rolls of film.
I checked a couple of websites to find the above prices. I didn't find prices to dev and scan sheet film, I'd guess most large format photographers do their own.
So, how much it costs depends on the format you use and how much you shoot. I'm by no means a prolific shooter. Personally, I would estimate that I go through somewhere around 50 sheets of 4x5 film and maybe 30 rolls of 120 film in a year on average. Toss in a couple of rolls of colour and some 35mm film and I would spend somewhere around $500.00 per year.
I develop, scan, and print at home so I don't pay for processing. I do buy chemicals and paper though so maybe add another $500.00 (it would be less). So, in total, I would spend less than $1,000.00 per year making photos.
Of course it's going to be a much different amount for someone else so your mileage may vary... 8x10 colour film at $38.00 per shot is going to add up very quickly.
If you owned $10k worth of digital gear, (which would get a decent body and a few lenses), and even if it is depreciating in value at only 10% p.a. then it is costing you $1,000 per year. That doesn't even consider the cost of things like spare batteries and memory cards that will likely lose 100% of their value. You'll probably throw them in when you sell the body to upgrade to the latest thing.
All things considered, I haven't found the cost of making film photos to be much different over time than when I was shooting digital. It is hard to put a value on doing something you enjoy, it's probably best not to think about it too much.