Fans who pay more have a right to expect more. Yes. It's not lunacy when the industry is drowning in cash.
I don't believe the Red Sox are entitled to a title or anything. But consumers of the Red Sox are charged higher prices than any other consumer base by any other team, and so fans rightly have higher expectations of the product. The team does not have to spend more than anybody else, but it is not wrong for consumers to expect that Boston act like a big market team, to be in on big free agents, to retain good players in their primes, all of that.
Fans should expect that the Red Sox would take a deadweight contract as a fair price to get a premium asset - heck, sometimes that deadweight contract becomes a World Series MVP - and to push their weight around smartly. Fans should rightly get upset when Sox management scolds them for wanting nice things.