But Harbour Air does, with regular and Atomic Beavers.

I've booked many many hours on floats and in real "seaplanes," in my case marvelous old Grumman Gooses (Geese?) with two honking radial engines and crank-me-up-crank-me-down landing gear for amphib operations. Wonderful old buckets of bolts. You'll never have as stirring a takeoff as you will in a Goose off the water in an Aleutian bay, with Orcas swimming like demons to get out of the way. Woo hoo.