I feel the opposite. Looking at the yearly revenue of these companies and dividing them by the number of people that contributed, I clearly created much more value than my comp gave me.
I learned pretty quickly that money in Silicon Valley has nothing to do with getting what you "deserve" after a co-worker sold a domain name at the height of the dot-com bubble and retired on the proceeds. Sometimes people get lucky and there's no point in getting angry about it.
Do you think it's reasonable Zuckerberg or Bezos get rewarded the way they do while Amazon drivers piss in bottles and barely paid contractors get PTSD from moderating Facebook?
The system is rotten to the core. We as tech workers are somewhere in the middle, simultaneously being exploited while also benefiting from the exploitation of others.
Would you rather people not be allowed to do these jobs at all? That wouldn't leave them better off. Even paying them more must necessarily be weighed against the opportunity of expanded hiring at the prevailing market wage, lest you simply create a new privileged high caste of super highly paid Amazon drivers or Facebook content moderators.
I think I have shown gratitude to all my employers. They have invariably treated me well, and I believe the relationships were mutually beneficial.
If you do not feel gratitude to your employer I suggest you find a different one. If you cannot find such an employer over an extended time frame, perhaps the problem is you.