When it comes down to it, the main reason is cost. Telcos (or any big business) HATE spending money, and if they feel they can get away without doing so they will.

I used to find this an issue and frankly I still do to a point, but I have found that small changes to the way that you do things can make a big difference. It all adds up in the end. For instance:
- Park further away from work so you get a bit of a walk in the morning and afternoon (not overly far, but say about 1-2km), it adds about 15 - 20 min to your day and helps to wake you up pre and post work.
- Change shopping habits, personally I live reasonably close to my local shops (about 500m), I have taken to buying long life things like soap and toilet paper in bulk using the car but walking to the shops every couple of days for food (and beer) and then only buying what I can carry back myself. This obviously will not work if you live far away from the shops but you get the idea.
- As others have said, changes in what and when you eat can help a lot. I moved from the usual fast food and high sugar diet to one that was a lot more balanced. So muesli in the morning instead of high sugar cereal or a bacon and egg roll, switching from soda and energy drinks to tea, coffee, or just water. In general just switching to less energy dense foods.
I've been working things like these into my life for a couple of years now and whilst I do slip up from time to time in general I stick to it. I wouldn't say that I'm fit but I'm in a lot better shape than I have been in years.