Where should the line be drawn between classes that are "protected" enough?
As I frequently tend to explain, hate speech is an attack on an unchangeable characteristic of an individual. Gender, sexual orientation, race/ethnicity, religion, disability, etc. - if it's something that can't be helped or can't fundamentally be changed, insulting someone on that basis would be hate speech.
Income and spending practice are very malleable characteristics. I could potentially have a job or other such source of income, and then one day I could leave off or get fired or something else; and likewise, I could be very open to spending one day, but then the next start being more careful about my purchases.
If we are to have freedom of choice, but we permit people to be harassed, demeaned, and insulted based on their choices, is it true freedom of choice?
Generally speaking, if that harassment and insult does not ultimately constrain a person's choice, then yes, it is still the freedom of choice.
The problem is that you're conflating all use cases of a disparaging term to being insults and harassment; it's still a shitty term, but as I mentioned before, it's an unfortunate effect of the euphemism treadmill. It's very difficult to remove negative connotations from something like excess spending.
It is possible, I'm certain, but you'd have to boil it down to the point where it becomes akin to Intellectual Disability; so reduced into a basic description that it would barely see any common use. And even then, people would still fall back on disparaging slang terms since the association is so ingrained on the word that it becomes part and parcel with the described subject.
So, like I said; it's a bullet we unfortunately have to bite.
There is absolutely no reason that discussing spending in excess should be permitted on the boards.
I disagree; there is, at least somewhere on the Boards, a place where Riot's pricing for content and the like belongs, and if there is any place where people are permitted to discuss things like pricing, commerce, and so forth, I think that there will also inevitably be a place where discussing/referencing excess-spenders is permitted.
If people are spending money on League through their own choices, it's their choice, and they should not be permitted to be harassed or insulted for it. It does not matter you disagree with their choice to spend - it's their choice, not yours.
I don't disagree in the slightest. I've been raised with the ethos of "(not) my money, (not) my problem" - people have no place to dictate or argue how someone else spends their money, and vice versa.
But I don't believe that "whale" as a broad-use term merits being completely disallowed.