Fuck the usps, no matter which state you are in the people who work at the post office are slow as fuck, they will take 5 minutes to sell a stamp. Having a cushy job with sweet benefits does not give them any incentive to work faster.
You must be exclusively literally be talking about the post office and not USPS as a whole. I dont know how much has changed, but there was nothing cushy about working in the distribution centers. Depending on where you worked youd be constantly moving and you could look at the people who'd work there for years and see the long term damage that was happening to their bodies.
Also not everyone who works for USPS is a permanent employee so they are not entitled to benefits. That being said there were permanent employees who bullshited alot because of the union. I was there in the early 2000s and from my understanding it was extremely hard to fire people, so you would have people taking advantage of the system. At the time I thought some people were lazy but in hindsight some people were working there since they were dam near kids. Again working a physically demanding job takes a toll on your body and it doesn't matter how much of a healthy lifestyle you live.
Because I was not permanent, I went for a interview with UPS and from what I observed I preferred USPS. The main benefit would have been the 4 hour schedule and I was in school at the time, but the environment looked little more harsher than USPS