
There are at least four ways to spell Finn's surname--apparently Forest Lawn, where he's buried, spells it "Frolick".... Anyway, Frolich/Froelich/Frohlich/Frolick added more than his remains to the cemetery. Besides his sculptures for Richfield, there was his Tower of Legends at Forest Lawn, which disguised a water tower and lasted from 1924 into the '40s (Finn himself expired in 1947). It is shown above at two Easter sunrise services, the second while still under construction (I love the futuristic spherical pods servings as forms or carving shelters over two of the monument's sculptures).
The tower is now the site of the Great Hall of the Crucifixion and Resurrection. The lower scultpure, "The Mystery of Life," still stands--it was done by Ernesto Gazzeri.
As for the Richfield advertising sculptures, some still exist (or at least copies of the originals, or pieces inspired by them):

And here is some random info from
Primarily Petroliana:
"The story of the Richfield Beacon Stations and Towers represent an important aspect of the early history of the Richfield Company. Richfield was established in 1915 by the merger of two small oil companies in Los Angeles, CA. They entered a competitive marketplace that was dominated by the “Big 4” of the oil industry, Standard, Shell, Associated and Union.
One of the ways that they chose to compete was to develop a more powerful gasoline. They were able to develop a gasoline with an octane rating of 75 which at that time was quite high.. To promote this more powerful gasoline they offered it to race car drivers around the LA area and by 1921 they were supplying their products for the racers at the Indianapolis 500. From 1921 to 1932 cars using Richfield gasoline took the top five places at Indy, which spawned there phrase, “Gasoline of Power”.
To celebrate this success a statue was commissioned in 1926 and created by sculptor Finn Haakon Frolich. This large statue featured a dirt track racer sliding through a turn and was used as a monument at various Richfield stations to commemorate their racing successes. A scaled version of this same statue was used on top of the pumps at the Beacon stations, along with a sculpture of an airplane in flight, which symbolized Richfield’s role in aviation fuel."
"[The original sculptures were] made from a plaster of paris type material, finished it a high luster, faux marble finsish. There were 2 sizes of these,
the smaller faux marble ones that were placed at the stations, and then the large bronze ones which were put along the highways to signal an upcoming station. The large ones were so massive that the entire foundry operation was moved from town to town, and the monuments cast as close to the permanent locations as possible, so that the huge monuments didn't have to be moved very far."
Top two pics:
LAPL; third from top:
FL Books; fourth and fifth:
Primarily Petroliana.