So in your culture one is supposed to be grateful for free things unquestioningly? Why does culture need to be brought into this? If, one day, churches started handing out rat poison to the hungry instead of food; are the hungry entitled to happily eat that rat poison because it is free?
The problem is that Firefox makes these promises and builds a platform (in this case, old-school XUL-powered extensions), builds a profitable user-base from said platform, and then yanks features at a whim. It is almost like a classic bait-and-switch but played in slow motion. In the case of Firefox there simply aren't suitable replacements available for many add-ons because the APIs and underlying features they relied on are being pulled. And they are being pulled because of managerial decisions, made to metrics that only highlight majority use-cases, in the name of "saving programmer bandwidth". As a result, a popular, powerful, useful program more and becomes more like a disposable appliance and less like an extension of the mind.
"Who cares about nice ideals like mind extensions blah blah blah" you think? Well, a lot of users do (especially us old nerds), many of us who have stuck by Mozilla and will willingly dance to their beat in exchange for the company's historical sense of economy in its asks and respect for its userbase.
If Mozilla were making Firefox out of the kindness of their hearts, maybe you would have an argument. But Mozilla is a million-dollar business and much of what has become of their flagship browser lately is a result of business decisions to bring in more money, so I have a hard time understanding how legitimate user complaints could be considered "entitled".