Why would creditors accept a comfort letter that can't be legally enforced, from borrowers that refuses to guarantee?
It's not as much a matter of reputation as much as it is a question of signaling. not paying one of your debts could signal to other suppliers that you are NOT ABLE to pay which will prompt them to stop any on-going deliveries and require much stricter payables conditions. These kind of things happen more often in companies facing difficulties. The apparent (real or fake) inability to pay could materialize into a number of headaches with other counter-parties and render you unable to follow up with any business if you just used this "excuse" to gain more time. There is an example where we recently saw this with TESLA in their relationship with Panasonic, turned out they just wanted to delay payments as much as possible but it raised a number of questions on their cash flow situation and ended up causing a lot of volatility (albeit temporary) in their listed liabilities (equities and bonds).