My ex-wife has worked in retail at all levels for 40 years. District managers intentionally force schedules to be broken up so breaks and lunches, outside of managers, are never needed. They intentionally over-hire to make sure they pay the absolute least amount. The average weekly schedule is 30-31 hours and those are broken up into 4 to 6 hour chunks. You may get a break if you're lucky. You may get a lunch if you're on for 8 hours. But the clear direction of the industry is to limit each worker to the least amount of hours, eliminate non-working time, and make sure benefits and overtime are never paid.
The ACA has absolutely nothing to do with employer based healthcare.
The cost of healthcare is the direct result of the creation of the HMO laws during Reagan's presidency, allowing hospitals and doctors to make pre-arranged profit oriented agreements that increased insurance costs.