This. The potential difference is huge.
One simple difference between buying your lunch at work every day and buying it once a week and taking leftovers or other food from home most of the time.
Say a coffee on the way to work and something mid priced such as McDonalds, Greggs or Pret for lunch, normal stuff, not the cheapest meal deal but not a sit down lunch. This costs £10 a day. Say your food from home costs £2.
£10 a day is £50 a week. Once a week plus food from home is £18 a week so a difference of £32 or about £130 pm. Or nearly £1500 per year, which is a very decent emergency fund, or £15k per decade, which will buy a good second hand car. Add in an average 5% interest and will be worth almost £20k in a decade.
All simply due to making a sandwich and getting coffee at work most of the time rather than buying it.
Repeat for some of the many many other ways there are to spend money or not on non essentials, or by taking a more expensive choice - more expensive car, mobile phone, pizza from the supermarket rather than delivery, not shopping around so paying full price and you can probably add a zero to those numbers. The difference can to add up to hundreds of pounds a month, often with little noticeable difference in lifestyle.
Most people (to be clear excluding those who's income does not cover their essentials) do have sufficient money to not be broke, all they have to do is spend less than they earn.