Congratulate yourself, because you are, for sure, a fortunate outlier! I don't doubt that there exist engineers out there making $250K+, but they are definitely not the norm, big company or small. Check out a bigger sample of Bay Area companies on Glassdoor. My bet is you'll find the middle 90% to be between, say, $90K and $150K.
Every level 5 (senior) engineer at Google and Facebook converge around $250k in total yearly income (probably more for facebook recently since their stock tripled in the past year).
Really? My starting salary as a level 1 engineer in the first dotcom boom was $115K. Now had I taken a more fun (but as it turns out in reality frequently not very fun) job in the game industry, that salary would have been ~$70K. This of course is an industry segment with its own crazy outliers.
Fortunately, someone sensible figuratively smacked me upside the head and convinced me to take a more practical job (which ended up pretty fun actually).